
With abortion on the Nov. 5 ballot, we look back at Steve Levitt’s controversial research about an unintended consequence of Roe v. Wade.
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Stephen Dubner
Hey there, It's Stephen Dubner. Two years ago, the U.S. supreme Court struck down Roe v. Wade, the court's 1973 ruling that made abortion legal throughout the U.S. with this new ruling, the legality of abortion was kicked back to the states. Since then, 13 states have banned abortion and eight others have imposed more limited restrictions. This election day, November 5th, voters everywhere will be choosing a president, and the voters in 10 states will also be considering ballot measures that aim to protect abortion access. Kamala Harris has said that if she becomes president, she would sign a bill to once again make abortion legal nationwide. Donald Trump's position is less clear. Harris says that Trump would sign a national abortion ban, but Trump has denied this and said the issue should be left to the states. Whatever the outcomes on Election Day, the fact is that abortion laws in the US Are in the middle of a big shift with consequences that are hard to predict. The law of unintended consequences Consequences isn't really a law, but it is at least a principle that we talk about a lot on this show. And there was one particularly noteworthy unintended consequence of Roe v. Wade that Steve Levitt and I wrote about in Freakonomics way back in 2005. We revisited this topic in 2019 in an episode of Freakonomics Radio. At that time, a lot of state legislatures, especially in the south and Midwest, were already moving to restrict abortions. Considering the state of play today, I thought it might be worth hearing that 2019 episode again. It's called Abortion and Crime Revisited. We have updated facts and figures throughout. As always, thanks for listening. When you think about unintended consequences, when you think about two stories that would seem to have nothing to do with each other, it is hard to beat the stories we are telling today. The first one, if you follow the news even a little bit, should be familiar to you. It concerns one of the most contentious issues of the day, new developments in the escalating battle over abortion. The last clinic in Missouri on the verge of closing today. The battle goes back at least to 1973, when the U.S. supreme Court took up a case called Roe vs. Wade.
Steve Levitt
The Supreme Court today ruled that abortion is completely a private matter to be decided by mother and doctor in the first three months of pregnancy.
Stephen Dubner
A few years before, Roe v. Abortion had been legalized in five states, including New York and California. The Supreme Court made it legal in all 50 states. But lately, several states have been pushing back hard.
John Donohue
The Ohio governor signing today what critics condemn as the most restrictive abortion law in the country.
Stephen Dubner
Nearly a dozen states are now imposing new restrictions this year, including. Meanwhile, if you go back 30 or 35 years, there was a totally different story dominating media coverage and the political conversation.
Steve Levitt
Let us roll up our slee to roll back this awful tide of violence and reduce crime in our country.
Stephen Dubner
We must take back the streets. If you weren't around then, it's hard to remember just how bleak the outlook was. Crime had begun to rise in the 1960s, continued on through the 70s and 80s, and by 1990, it seemed that everyone was scared everywhere all the time.
Steve Levitt
Robberies, assaults and even murder have replaced shoplifting, vandalism and truancy.
Stephen Dubner
Crime became a top prior among Democrats.
Steve Levitt
It doesn't matter whether or not they.
Stephen Dubner
Were deprived as a youth and Republicans too. There are no violent offenses that are juvenile. You rape somebody, you're an adult. You shoot somebody, you're an adult.
Steve Levitt
Experts call them super predators.
Stephen Dubner
Everyone agreed that violent crime was out of hand, that the criminals were getting younger, and that the problem was only going to get worse.
Jessica Walpole Reyes
There's a tidal wave of juvenile violent crime right over the horizon.
Stephen Dubner
But the problem didn't get worse. In the early 1990s, violent crime began to fall. And then it fell and fell and fell some more. Consider New York City. In 1990, there were more than 2,200 homicides. In 2023, there were fewer than 400. But it wasn't just New York. With a few exceptions, crime across the US has plunged. Why? What led to this unprecedented and wildly unexpected turnaround? Everyone had their better policing, the reintroduction of capital punishment, a stronger economy, the demise of the crack epidemic. Meanwhile, a pair of academic researchers came up with another theory. It was surprising, it was jarring, but it seemed to hold great explanatory power.
Steve Levitt
And he said, well, I think maybe legalized abortion might have reduced crime.
Stephen Dubner
If you've ever read Freakonomics, the namesake book of this show, you may recall this controversial link between legalized abortion and the fall of crime. Today on Freakonomics Radio, the story behind the research and evidence for the theory, the challenges to its legitimacy, and the results of a new follow up analysis.
Steve Levitt
It was completely obvious to us that a sensible thing to do 20 years later would be to look and see how the predictions had turned out.
Stephen Dubner
How did they turn out? What does this mean for abortion policy? What's it mean for crime policy? We'll get to all that right after this.
John Donohue
This is Freakonomics Rad, the podcast that explores the hidden side of everything with your host, Stephen Dubner.
Stephen Dubner
From 1991 to 2001, violent crime in the US fell more than 30%, a decline not seen since the end of Prohibition.
Steve Levitt
I was spending most of my waking hours trying to figure out this puzzle about why was it the crime, after rising for 30 years from 1960 to 1990, had suddenly reversed?
Stephen Dubner
It's Steve Levitt, my Freakonomics friend and co author. He is an economist at the University of Chicago. He's always had an intense interest in crime.
Steve Levitt
I had looked into all of the usual suspects, policing and imprisonment, the crack epidemic. But really, you could not and you cannot effectively explain the patterns of crime. Looking at the kinds of components that people typically talk about when they try to understand why crime goes up and down.
Stephen Dubner
Leavitt eventually wrote a paper called Understanding why Crime fell in the 1990s. Four factors that explain the decline and six that do not. The six factors that, according to his analysis, did not contribute to the crime drop a strengthening economy, the aging of the population, innovative policing strategies, gun control laws, right to carry laws, and the increased use of capital punishment. While each of these in theory might seem to have some explanatory power, Leavitt found they didn't. The relationship between violent crime and the greater economy, for instance, is very weak. Capital punishment, he found, at least is currently practiced in the US Simply didn't act as a deterrent against future crimes. Then there were the factors he found did contribute. The increase in the number of police, an increase in the number of criminals imprisoned, and the decline of the crack cocaine trade, which had been unusually violent. But these three factors could explain only a portion of the massive drop in crime, perhaps only half. It was as if there was some mysterious force that all the politicians and criminologists and journalists weren't thinking about at all.
Steve Levitt
I had the idea that maybe legalized abortion in the 1970s might possibly have affected crime in the 1990s.
Stephen Dubner
One day, paging through the Statistical Abstract of the United States, which is the kind of thing that economists like Levitt do for fun, he saw a number that shocked him.
Steve Levitt
At the peak of US abortion, there were 1.5 million abortions every year.
Stephen Dubner
That was compared to roughly 4 million live births. The sheer magnitude of abortion surprised Leavitt, and he wondered what sort of secondary effects it might have. He wondered, for instance, if it might somehow be connected to the huge drop in crime.
Steve Levitt
And I had actually gotten obsessed with the idea and had spent maybe three weeks working around the clock, and I had decided that the idea wasn't a very good one, that it didn't make sense. And I had a huge file of papers that I had put away and had moved on to another project.
Stephen Dubner
Leavitt, like a lot of researchers, was juggling a lot of projects with a lot of collaborators. One of his collaborators was named John Donohue.
Jessica Walpole Reyes
Yeah, and I'm a professor of law at Stanford Law School.
Stephen Dubner
Donahue also had a PhD in economics, so he and Leavitt spoke the same language. Donahue was particularly interested in criminal justice issues. Gun policy, sentencing guidelines, things like that. For instance, he found that minorities who kill whites receive disproportionately harsher sentences in Connecticut. This research ultimately led to changes in that state.
Jessica Walpole Reyes
Yeah, it clearly played a role in the initial legislative decision to curtail the death penalty in Connecticut, as well as in the final Connecticut Supreme Court decision abolishing the death penalty.
Stephen Dubner
Donahue had been doing a lot of thinking about the rise in crime starting in the 1960s. He thought the drug trade was one big factor.
Jessica Walpole Reyes
Yeah, it does seem that large illegal markets are important contributing factors to crime. It was also a time of great flux around the Vietnam War. And, of course, the Vietnam War had multiple influences that contributed to social unrest. And at the same time, there was pressure going in the opposite direction to try to reduce the harshness of punishment and perhaps pull back a little bit on elements of policing. And so the combination of those factors, I think, exacerbated the crime rate.
Stephen Dubner
So one day, John Donahue and Steve Levitt were sitting in Levitt's office.
Steve Levitt
And I remember, like, yesterday, John says, you know, I have the craziest idea. I mean, it's, like, totally absurd. And I said, oh, what is it? And he said, well, I think maybe legalized abortion might have reduced crime in the 1990s. And I said, that's so funny. And I reached into my filing cabinet, I pulled out this huge, thick thing, and I slammed it down on the desk.
Jessica Walpole Reyes
Yeah, that's right. When I talked to Steve about it, as is often the case, since he is such a creative mind, he said, oh, yeah, you know, I wondered about that.
Steve Levitt
I said, I had that same idea, but it's not right. And he said, well, what do you mean? And I walked him through my logic, and I hadn't thought deeply enough about it. And I had been focusing on the fact that when abortion became legal, there was a reduction in the number of children born. And John said, yeah, but what about unwantedness? And I'm like, what do you mean, unwantedness?
Stephen Dubner
What did Donahue mean by unwantedness? He was referring to the expansive social sciences literature, which showed that children born to parents who didn't truly want that child or weren't ready for that child. Those children were more likely to have worse outcomes as they grew up, health and education outcomes. But also these so called unwanted kids would ultimately be more likely to engage in criminal behaviors. Donohue had begun to put the puzzle together when he attended a conference.
Jessica Walpole Reyes
And I heard a paper being presented at the American Bar foundation by Rebecca Blank, who's a distinguished economist.
Stephen Dubner
Blank spent nine years as chancellor of the University of Wisconsin, Madison. When we were making this original episode back in 2019, she declined our request for an interview. Blank died at age 67 in 2023.
Jessica Walpole Reyes
And she was talking about who gets abortion in the United States, that is.
Stephen Dubner
After Roe v. Wade. What were the characteristics of the women most likely to get an abortion?
Jessica Walpole Reyes
And she was highlighting that it was poor, young, unmarried, inner city, minority women. And as I was looking at the elements of crime in the US There was quite an overlap between the populations that were involved in this increase in crime with the group that she was identifying as a group of women who were most likely to be experiencing higher rates of abortion. And so that got me thinking about, could abortion actually influence crime rates?
Stephen Dubner
Did that initial thought even make you a little uncomfortable? Because it's pretty obvious to just about anyone that that's sort of a third rail idea.
Jessica Walpole Reyes
Yes, I knew that this would be very electric to some individuals, but for me, I was really interested in studying the impact on crime that we were observing at that particular moment. And so it didn't inhibit me at all because I thought there is an issue here, and it's useful to be able to figure out what the truth is.
Stephen Dubner
How did the population of women who were having abortions change from before Roe v. Wade, or really from before abortion was legalized state by state to afterwards?
Jessica Walpole Reyes
Yeah, that's a great question. And of course, there's much that we don't know about what was happening before because of the illegal nature of abortion in most states. But we can sort of infer from the changes that did occur and the fact that some states legalized in 1970 and became avenues for travel to have abortions done. We can sort of piece together who was traveling to have abortions and see how things changed when then abortion became legal everywhere. And so one thing that we did see is that affluent women did travel to have abortions in the period between 1970, when New York legalized, and 1973, when Roe vs Wade was decided. But it involved travel and expense and therefore was too much of an impediment for the group of women that we are most interested in, which are the ones who are usually at the lower end of the socioeconomic scale and did not have the opportunity and resources that would permit them to travel.
Steve Levitt
So then John and I just spent a little bit of time making back of the envelope calculations of how important this unwantedness effect could be be, and it was really shocking.
Stephen Dubner
Remember, the magnitude of abortion was huge. At its peak, there were 345 abortions for every 1,000 live births.
Steve Levitt
And so when you took the magnitude and you interacted with this very powerful unwantedness effect that's been documented elsewhere, it actually suggests to us that abortion could be really, really important for reducing crime 15 or 20 years later.
Stephen Dubner
The mechanism was pretty simple. Unwanted children were more likely than average to engage in crime as they got older. But an unwanted child who was never born would never have the opportunity to enter his criminal prime 15 or 20 years later. Donohue and Leavitt created a tidy syllogism. Unwantedness leads to high crime. Legalized abortion led to less unwantedness. Therefore abortion led to lower crime. But syllogisms are easy. What about evidence?
Steve Levitt
So it's not that easy to convince people that there's a causal impact of legalized abortion on crime, because this is certainly not a setting in which I'm ever going to be allowed to, say, run a randomized experiment in which I decide who does or doesn't get abortions. And so instead, what we have to do by necessity, is to look at a collage of evidence. So a bunch of different, all quite imperfect sources of variation that allow us to get some sense of whether there might be some causality between legalized abortion and crime.
Stephen Dubner
So Levitt and Donohue set out to assemble this collage of evidence.
Steve Levitt
The first one we look at relates to the fact that before Roe vs. Wade, there were five states who had already legalized abortion in some way, shape or form. And these were New York, California, Washington State, Alaska and Hawaii. So unfortunately, not the states you would want to say are a representative set.
Stephen Dubner
Of states, because why?
Steve Levitt
Well, they're all liberal. I mean, so Alaska and Hawaii is weird. They're not very helpful at all. New York and California are on the cutting edge. Now, one thing that's really important to stress is that the states that legalized abortion earlier didn't just get a five year head start on the legalization of abortion before Roe V, they actually were states that had many, many more abortions, a much higher abortion rate than the other states. So if you look at the data. Now, these states even today have abortion rates that are almost double the abortion rates of the rest of the U.S. which again, I think points out how poor it is as a natural experiment.
Stephen Dubner
Given that limitation, it wouldn't be enough to just measure the crime rate in the early legalizing states and compare them to the rest of the states. You'd want a more precise measurement.
Steve Levitt
So we divide states into three equal sized groups. The highest abortion rate states, the medium abortion rate states, and the lowest abortion rate states. And then we just look at those three groups and we track them over time. What happened to crime? And so we're able to look and see, well, is it really true that the highest abortion states and the lowest abortion states had similar crime trends when you expected them to have similar crime trends? And it turns out in the data that that's exactly right. We found that there was roughly a 30% difference in what had happened to crime between the highest abortion states and the lowest abortion states by 1997.
Stephen Dubner
That seemed to be firm evidence in support of the thesis. Now, Donohue and Levitt looked at crime data state by state by age of offender.
Jessica Walpole Reyes
So the nice thing in the data that we had available was we could look at arrest rates by single age of individual.
Steve Levitt
So if I'm born in 1972 in Minnesota, well, I probably live a pretty similar life to someone who's born in 1974 in Minnesota in terms of other things like policing or drugs or other things in the environment. But the difference is that those who were born in 1974 were exposed to legalized abortion. Those who were born in 1972 weren't. And we find numbers there that are completely consistent with the rest of our analysis, that those who are born just a few years apart do much less crime than those who were born in the earlier years.
Jessica Walpole Reyes
Because the abortion rates were rising so Sharply in the 70s, these cohorts were coming into their crime ages in a stacked fashion. And we could identify which abortion rates were associated with each particular age. And the higher the abortion rate was for each age, the greater the crime. Crime drop occurring.
Stephen Dubner
So as you're putting together this collage of evidence, what did it feel like to see the strength of this evidence of the link between legalized abortion and crime? Did it immediately suggest policy or political or healthcare follow ups?
Jessica Walpole Reyes
Steve and I, I think both had this sense of something really unusual has suddenly happened in crime in the United States, and we really just want to understand what that is. I really wasn't thinking about the way in which this would be received. I really just wanted to understand, is this a factor that has altered the path of crime in the United States?
Stephen Dubner
Leavitt and Donahue would go on to publish their paper, the Impact of Legalized Abortion on crime in the May 2001 issue of the Quarterly Journal of Economics. What happened next? That's coming up after the break. Legalized abortion appears to account for as much as 50% of the recent drop in crime. That was the stark finding of a study published in 2001 by Steve Levitt and John Donahue. But even before the paper was published, their findings hit the news.
Jessica Walpole Reyes
It was a whirlwind of reaction, and some of it was a little unnerving because people were reading into the study things that we certainly did not intend.
Steve Levitt
Everybody hated it. People who are in favor of right to life were upset because our argument seemed to be endorsing the idea that legalized abortion had positive effects. But many people who believed in the right to choose, they were also upset because we were kind of saying, well, you're killing these fetuses so they never get a chance to grow up to be criminals. The number of death threats that I got from the left was actually greater than the number of death threats I got from the right, because the other thing that emerged out of the media coverage is that it very quickly became a question of race, Even though really our paper wasn't about race at all.
Jessica Walpole Reyes
Some people started to say that, you know, we were trying to go back to the times where people were pushing for control of the fertility of certain groups and maybe even racial groups. And that was certainly not anything that we even considered. We were just trying to figure out when public policy had changed in this profound way. Did it alter the path of crime? We certainly weren't eugenicists, as some people initially argued.
Stephen Dubner
Initially, perhaps. But recently, too, in 2019, the US Supreme Court turned down an abortion related appeal from Indiana. But Justice Clarence Thomas, in an accompanying opinion, wrote, quote, some believe that the United States is already experiencing the eugenic effects of abortion. His citation, Freakonomics. Whether accurate or not, he continued, these observations echo the views articulated by the eugenicists and by Planned Parenthood founder Margaret Sanger decades earlier.
Steve Levitt
I actually think that our paper makes really clear why this has nothing to do with eugenics. In our hypothesis, what happens is that abortion becomes legal. Women are given the right to choose. And what our data suggest is that women are pretty good at choosing when they can bring kids into the world who they can provide good environment, it's for, okay? And so the mechanism by which any effects on crime have to be happening. Here are the women making good choices. And I think that's such a fundamental difference between women making good choices and eugenics, which is about the state, say, or some other entity forcing choices upon people. Almost couldn't be more different.
Stephen Dubner
Still, the Donahue Levitt argument linking abortion and crime was disputed on moral grounds, on political grounds, and on methodological grounds.
Steve Levitt
Very soon, there was a torrent of critiques and other academics trying to publish papers saying we were wrong.
Stephen Dubner
One critique came from Christopher Foote and Christopher Getz, two economists who were then with the Federal Reserve bank of Boston. They argued that Donohue and Levitt's paper contained a coding error which, when corrected, blunted their findings.
Steve Levitt
So, in general, I don't mind challenges to my work, but I hate it when the challenges take the form of mistakes. And that is an awful, awful feeling to have made a mistake, which we did in this case.
Stephen Dubner
What exactly was this error and how did it happen?
Steve Levitt
So John Donahue and I started working on this paper probably in, I don't know, 1996, and it finally came out in 2001. And when you write an academic paper, you go through a refereeing process. And the refereeing process we went through was especially brutal. So an enormous effort of time. Look, we were tired and we were burned out. And one of the last things in those referee reports said, you should add a table to your paper that looks very specifically by single year of age. Okay? So we initially, when we submitted our paper, had six tables in the paper, and we had thought of doing something that looked very specifically by single year of age, but we hadn't done it. But the referee suggested we do it. And it was actually a really good, sensible suggestion. And so what we did was, in a very tired, quick way, we added Table seven to our paper, which turns out supported our paper. But we didn't try very hard. We didn't really do it right. We just threw something together and it worked. And so it turned out what Foot and Gets then were responding to was that what we said we did in Table 7 wasn't actually exactly what we did. We said we had included a particular set of interactions. We had actually run those regressions. Just when the numbers got translated into the table, a different set of columns got put into the table.
Jessica Walpole Reyes
The error was almost more in the description of the paper rather than an actual mathematical error. So we had said that we had controlled for state year effects in our paper, which is sort of an econometric point of terminology when it was only a state effect that we had controlled for. And so it did weaken the result, although did not fundamentally alter the conclusion.
Steve Levitt
I didn't feel like the foot and guess critique was very damaging to the hypothesis. It was certainly damaging to me and my reputation because I had made those mistakes. But the hypothesis, I think, comes through in flying colors.
Stephen Dubner
But by the time Donohue and Leavitt corrected their work and found that the correction did not weaken their hypothesis, the headlines had already been written.
Jessica Walpole Reyes
And so people made a lot of, oh, there's a mathematical error here, which wasn't quite right.
Steve Levitt
We really, in some ways lost the media battle because we looked stupid, because we had made the mistake.
Stephen Dubner
The headline in the Economist, oopsonomics in the Wall Street Journal, freakonomics, Abortion research is faulted by a pair of economists.
Steve Levitt
It was fun for people to jump on the bandwagon of attacking just because nobody really liked the hypothesis in the first place. And so the silver lining on Foot and Getz pointing out the mistake is that it actually gave us the opportunity to go back and take care of the measurement error that was in the data and to actually think sensibly about it. And so when we did Table seven the right way, even correcting for that mist we made in the initial paper, the results are actually stronger than ever.
Stephen Dubner
To be fair, you can understand why the Leavitt and Donahue argument is an uncomfortable argument. No matter where you stand on abortion or crime, it attaches a positive outcome to an inherently unhappy input. It creates an awkward pairing of an intimate, private decision with a public utilitarianism. So even while their argument was empirically strong and their cause and effect mechanism plainly logical, it might be discomforting to fully embrace it, especially when other more comforting theories present themselves.
John Donohue
My name is Jessica Walpole Reyes, and I am a professor of economics at Amherst College, and I study the effects of environmental toxicants on social behavior.
Stephen Dubner
One toxicant Reyes focused on was lead pollution.
John Donohue
There is a huge literature on how lead is toxic to humans. Lead has cognitive health and behavioral effects. So lead is associated with reductions in iq. It's associated with increased behavior problems in children. It also has health effects, cardiovascular effects, renal effects, and it's just really, really bad.
Stephen Dubner
So bad that lead could be a causal factor in criminality. In other words, exposure to lead in childhood could lead to criminality in adulthood. Two big sources of environmental lead in the old days were gasoline and paint.
John Donohue
And the reason I was thinking about lead was I was pregnant with my son, and we lived in this really old house and we needed to move. Right. I knew that lead was bad, but I started thinking about, huh.
Stephen Dubner
As with the abortion thesis, which used Roe v. Wade as a natural experiment, Reyes lead idea had a similar fulcrum point.
John Donohue
So, yeah, lead was taken out of gasoline under the authority of the EPA, under the Clean Air act in the early 1970s, the EPA mandated a timetable. That timetable was changed a little and delayed, but it ended up that lead was phased out of gasoline from 1975 to 1985. There are some important kind of corporate political dynamics, so the different companies did this differently. It wasn't driven by state policy. And that's really important that it wasn't driven by state policy, because that helps provide a valid natural experiment so that you have different states experiencing different time patterns of lead exposure.
Stephen Dubner
Like Donohue and Leavitt, Reyes was able to assemble a collage of evidence linking the removal of lead in different places and different times with the decline of crime in each place. She published her findings in 2009, arguing that the removal of lead under the Clean Air act was, quote, an additional important factor in explaining the decline in crime in the 1990s. Did her paper refute the Donahue Levitt conclusions about abortion and crime?
John Donohue
My paper does not refute their conclusions. To the contrary, it actually reaffirms them. I include their abortion measure in my analysis, and I find that the abortion effect is pretty much unchanged when one includes the lead effect, that the two effects are operating relatively independently and that each one is of similar magnitude when you do or don't account for the other. So what that means is that from my perspective, I think both stories are true and we can hold both of them kind of side by side. It doesn't make sense to look for a single explanation for a decline in crime. There are lots of explanations.
Steve Levitt
So Jessica wrote a really interesting and careful paper that tries to look at patterns in leaded gasoline and relate them to crime.
Stephen Dubner
Steve Levitt again.
Steve Levitt
And I'd actually distinguish between the very thoughtful, careful work that she did from some of the other work on lead, which I think is not nearly so good. It's funny that people argue there can only be one cause to why crime went down. And if lead's true, then it can't be abortion. Look, the world is complex and there could be many things going on.
Stephen Dubner
Indeed, this is how many academic researchers and lots of other scientists generally think about the world. It's called multivariate causality. That is almost no effect, has only a single cause all the time, which is why percentages and probabilities are useful. They express the magnitude of various causes. But here's the thing. A lot of people who drive the public conversation these days, especially politicians and journalists, they don't seem very comfortable with the notion of multivariate causality. Why not? It may simply be that this versus that stories make for better headlines and campaign slogans. Maybe it's because a lot of people who wind up in journalism and politics are not, shall we say, numerically inclined to the point where percentages and probabilities are a bit intimidating. In any case, what's a layperson to do if you're trying to make sense of a debate over complex issues like this?
Steve Levitt
I think it's really hard. I think it's really hard for a layperson to be able to watch a scientific debate or a social scientific debate, especially one that's being mediated through newspapers and magazines and blogs, so much being lost in translation, and figure out what's really true. It's not even easy for me as an academic. And I think there's a much more intelligent way to discuss social scientific research than is done now. So right now, maybe the most interesting way to portray an idea is to talk about the hypothesis and then, almost absent a lot of discussion of data, ask people to make a judgment about whether the hypothesis is true. I actually think we should flip that discussion on its head. If we want intelligent laypeople to be able to make good choices about what they believe and don't believe, then the basic premise has to start not necessarily from the hypothesis, but from the data. And so if the way that social science was reported was to say, here are the five facts that are true about the world, and then what those mean are up to people to agree upon. But that's never the way that discussions happen. Maybe because it's not interesting, maybe because it's a little too complicated, maybe it takes too much time, But I think there's actually a lot less disagreement about facts than about the interpretation of the facts. And so I believe that for an educated layperson, given a set of facts, they can make a better judgment about how to interpret those facts than the current way the media treats things, which is to often not talk about the facts, but just to talk about the interpretations and often to focus on, you know, really extreme emphasis on minor differences.
Stephen Dubner
With that in mind, Steve Levitt and John Donahue have added a new set of facts to the abortion conversation. They went back to their original abortion crime analysis from roughly 20 years ago and plugged in the updated data coming up in a minute. We'll hear what they found and what sort of policy recommendations it may suggest. We'll be right back. In 2001, the economist Steve Leavitt and the Economist legal scholar John Donahue published a paper arguing that the legalization of abortion in the US in 1973 accounted for as much as half of the nationwide reduction in crime a generation later. Here's Leavitt.
Steve Levitt
So the abortion hypothesis is quite unusual among typical economic ideas in that it makes really strong and quite straightforward predictions about what should happen in the future. And the reason it has that characteristic is because we knew already when we published our paper in 2001, how many abortions had been performed. And because there's a 15 to 20 year lag between performing the abortion and the impact on crime, we could already make strong predictions about what would happen to crime 15 to 20 years later. And so it was completely obvious to us that a sensible thing to do 20 years later would be to look and see how the predictions had turned out.
Stephen Dubner
Okay, so you and John Donahue did revisit this study. You just released an update to that 2001 paper, and this one's called the Impact of Legalized Abortion on Crime over the Last Two Decades. Did your prediction turn out to be true? False. Somewhere in the middle, when we revisit.
Steve Levitt
The exact same specifications. But looking from 1997 to 2014, it turns out that a very similar pattern emerges. The states that had high abortion rates over that period, that 30 year period, have crime rates that have fallen about 60% more than the states that had lowest abortion rates. I mean, these are really massive changes.
Jessica Walpole Reyes
And lo and behold, the results were substantially stronger than they were in the 2001 paper. So that was an interesting and noteworthy finding.
Steve Levitt
Now, the amazing thing, and the thing that really almost gives me pause is how enormous our new paper claims the impact of legalized abortion is. Because the cumulative effect over the last 30 years, if you just look at our numbers, suggests that abortion might explain something like 80 or 90% of the entire decline in crime. The effects implied by our data are so big that I actually think it will make people more rather than less skeptical about what's going on. Because it's almost mind boggling that a factor that's so removed from the usual set of things that we think about influencing crime may have been such an enormous factor.
Stephen Dubner
What would happen if you'd found the opposite, that the impact of abortion on crime 20 years later had disappeared? I mean, this is your most famous research. What do you think you would have done?
Steve Levitt
I don't know. Human nature says maybe we would have tried to hide that, like people make bad predictions try to hide it. But I would hope that we would have published the paper anyway. Because the thing is, if we didn't publish it, someone else would have published it. One of my first rules of doing research is when you find out you're wrong, it's much better to kill your own theory than have someone kill your theory.
Stephen Dubner
You know, a lot has changed since 1973 beyond abortion policy and abortion laws, access to birth control and many other factors that may intersect or not with crime. Causal factors. So I am curious whether you feel, you know, in your new paper, you do make clear that the effect is larger now, turned out to be larger than you had predicted. Do you think it will continue to hold forth? Or is the world, this complex world we live in, changing enough so that the effect of abortion on crime will diminish over time?
Jessica Walpole Reyes
There are lots of moving parts to this story. So one moving part is that there are other technologies for terminating pregnancies other than therapeutic abortions that may play a bigger role. So, for example, you can actually go online and buy pills that can induce miscarriages. And so you might be seeing some movement in those directions. And presumably the greatest thing that could happen in this domain is if you would eliminate unwanted pregnancies in the first place. But American policy has not been nearly as effective in achieving that goal. A country like the Netherlands, which has really tried to reduce unwanted pregnancies, has probably had the right approach in dealing with the issues that our research at least raised. So they have much, much lower rates of abortion, even though abortion is completely legal in the Netherlands. But they want to stop the unwanted pregnancies on the front end. And I think almost everyone should be able to agree that that is the preferable way to, you know, focus policy, if one can.
Stephen Dubner
It's worth noting that the term unwanted pregnancy is probably way too imprecise to describe the individual choices made by individual people. There are of course, many reasons why a given woman may decide to have or not have a baby. So if you're thinking about policy ideas, it probably makes sense to consider all these reasons and the nuances attached to each. That said, said, so called unwanted pregnancies have been falling in the U.S. consider teenage pregnancies, the vast majority of which are unplanned, if not necessarily unwanted. The teen pregnancy rate has declined by more than 75% in the past 30 years. The abortion rate has also fallen significantly at the peak you Will recall there were around 1 1/2 million abortions a year, compared to 4 million live births. That was in 1990. As we noted earlier, some states have banned abortion lately, and some states have upcoming votes on whether to keep abortion legal. Back in 2019, when I spoke with Steve Levitt and John Donahue, I asked them to talk about the link between abortion laws and crime.
Steve Levitt
So if indeed these states are making abortions much harder, harder to get, then our study, our hypothesis unambiguously suggests that there will be an impact on crime in the future.
Jessica Walpole Reyes
You can imagine that if a state were to really clamp down on abortions, but neighboring states permitted abortion, you would get some of this traveling to an abortion provider. But since that would tend to have a disproportionate effect on lower socioeconomic status, you might see exactly the problem that we have identified, that the children that are most at risk because they're unwanted pregnancies would be the ones most likely to be born once these restrictions are imposed.
Steve Levitt
On the other hand, I don't think anyone who is sensible should use our hypothesis to change their mind about how they feel about legalized abortion. So it really isn't very policy relevant. If you're pro life and you believe that the fetus is equivalent in moral value to a person, well, then the trade off is awful.
Stephen Dubner
What does he mean by an awful trade off? Remember, there are still around a million abortions a year in the US And.
Steve Levitt
John Don, you and I estimate maybe that there are 5,000 or 10,000 fewer homicides because of it. But if you think that a fetus is like a person, then that's a horrible trade off. So ultimately, I think our study is interesting because it helps us understand why crime has gone down. But in terms of policy towards abortion, I think you're really misguided if you use our study to base your opinion about what the right policy is towards abortion.
Stephen Dubner
But let me ask you this. If someone wants to use this research to consider policy, you're implying that the policy that they should think about is not abortion policy, but some kind of child welfare policy. What would that be? I mean, that's obviously a much less binary and much harder question, but what kind of policy would be suggested?
Steve Levitt
So I think there are two policy domains for which this research is important. Let me start actually with the obvious one, which is crime. We spend enormous amounts of money on police and prisons and other programs. We incarcerate millions of people, and much of the justification for that comes from the idea that those are effective policies. For reducing crime. So I think that's actually the most obvious implication of our paper, that if it's really true that most of the decline in crime is due to legalized abortion, then it brings real caution to the idea that a super aggressive kind of policing and incarceration policy is necessarily the right one to pursue. But the second one really does relate to the idea that if unwantedness is such a powerful influencer on people's lives, then we should try to do things to make sure that children are wanted. You could at least begin to think about how you would create a world in which kids grow up more loved and more appreciated and with brighter futures. And is that better early education? Is that permits for parents or training for parents, or minimum incomes? Who knows what the answer really would be? But there's a whole set of topics, I think, which are not even on the table.
Stephen Dubner
Levet, how do you work generally or most often? Do you have a thesis and go looking for data to support or dispute the thesis, or do you look for interesting data and see what hypothesis emerges?
Steve Levitt
It turns out in this particular case, John Donough and I had a hypothesis and then we went to the data. But that's pretty rare in economics and social sciences. Often either you start with the data or a set of patterns, and then you build the theory back from that. Or often what happens is you have a theory, you have a hypothesis, and you go to the data and then you're wrong, but you've still looked at the data, you still have a lot of interesting patterns in the data, and then you go back and you reconstruct a new hypothesis based on what you've seen. And actually, one of the things that that troubles me most about the way that academic economics happens is that there's this complete fiction in the way we write our papers and that economists write up our research as if we rigorously follow the scientific method, that we have a hypothesis and then we come up with a set of predictions, and then we test those predictions and then they almost always come true by the time we write the paper, because you only include as your hypothesis the one that is supported, even if it turns out it's your seventh hypothesis and your first six got rejected.
John Donohue
When you're doing research, you're somewhat attached to your hypothesis, but you need to try to keep it at arm's length.
Stephen Dubner
That again, is Jessica Walpole Reyes, who wrote about the link between crime and lead pollution.
John Donohue
You should be trying to figure out what is true. So I think that the complexity of what we do, the Fact that we use all of these econometric techniques to figure out these complex situations makes it suspicious to people, right? It's sort of like this magic thing we're doing, and then we come out with results. So I completely understand that. And the number of times people have said, well, you know, correlation isn't causation. Yes, we know. That's what we do, right? We take things, we start with a correlation. We're like, huh, I wonder if that's causal. How can I figure out, is that causal? Where can I find some variation in something that drives the thing that I want to see if it affects? I still find it really difficult to explain fully what we are doing when we are separating correlation from causation. And I even find it like my family, I can't convince them. They're like, yeah, well, you know, whatever. I mean, they sort of buy it after a while, but it takes a long time. And I think it's reasonable for people to say, I don't know what you're doing. You're doing something complicated and fancy, and then you're saying you've done something that seems implausible.
Steve Levitt
What we should do, I think, is first just settle on the facts. I think a great approach is not to say, here's my hypothesis. A great approach is to say, here's what we know about the world. Here are the seven facts.
Stephen Dubner
I wonder if we take it away from this abortion crime issue specifically, though, and think about any other really contentious issue, climate change, income inequality, gun control, et cetera. And you see how people make very, very strident arguments, often, as you said, not really using a fully considered set of the data. I wonder if it has to do with the fact that the issues themselves and the causal mechanisms underneath them are actually kind of less important to people than the tribal affiliation with a position.
Steve Levitt
I think there's a lot of validity to that argument. I think that many of these contentious issues, as you noted, they're ultimately not so much about utilitarian arguments, and I think that's fair. Obviously, it matters a lot to know whether humans are actually responsible for climate change, because it's silly to radically change everyone's behavior if we're not responsible for it. So there's an enormously important role for science in understanding those causal mechanisms. But in terms of the public debate and what people believe, I think you're absolutely right. That oftentimes what we believe is driven not by the exact facts, but by our conception of what kind of person we are or how we want the world to be. It's a discussion about right or wrong. And it would be useful if people remembered and were able to put, okay, I'm putting my right and wrong hat on as I talk about this, or I'm putting my scientific hat on as I talk about exactly how much the world is warming. And those are both very important conversations to have. Where I think we get lost is when we are having a conversation which confounds scientific and right and wrong issues or confuses them or mixes them. And it's hard for people to make that distinction.
Stephen Dubner
I know that you pride yourself, Levitt, on not being a right or wrong guy, but I am curious how being the author of this theory and paper has informed, if not changed, the way you think about the issue, particularly of children, of wantedness and unwantedness. And for the record, we should say that you have six kids, so plainly you're in the pro kid camp and you want them. Has this entire arc of the story, the early paper, the dispute, your relitigation of it, has this changed at all your thinking about the nature of why people have children and what we do with them after we have them?
Steve Levitt
So that's a pretty profound question. Let me answer a very narrow aspect of that question. So if there's one thing that comes out of our research, it is the idea that unwantedness is super powerful. And it's affected me as a father in the sense that I think when I first was having kids, I didn't feel maybe so obligated to make children feel loved. And it's interesting that now as I go through a second round of kids, I'm not trying to teach my kids very much. I'm just trying to make them feel incredibly loved. And it seems to me that that's a pretty good premise for young kids. And look, I don't know, is that because I wrote this paper on abortion and crime? Maybe partly, maybe partly not. But it does seem to me a very powerful force. And there is something so incredibly tragic to me about the idea that there are kids out there who aren't loved and who suffer. And look, it's backed up, I think, by our data that that leads them to tough things in life. I really think I've gotten very mellow in old age. I was. It was funny. I was. I was like a super rational, calculating kind of person. And as I've gotten older, I've just gotten very soft and friendly and nice and I never would have imagined that I would be so accepting of my teenagers and their various foibles. But it's funny, you know, I'm a really different person than I used to be.
Stephen Dubner
And is this a product of just aging or of something else?
Steve Levitt
I don't think so. I think sometimes when people get older, they get mean and sometimes they get nice. I'm not sure why I got nice instead of mean, but I somehow became more human. You know me, like I'm not exactly completely human. Like I'm lacking some of the basic things that many humans have. But I think somehow I'm growing more human traits over time. Don't you think?
Stephen Dubner
I do. I do. I definitely do. But I'm curious. What's the causal mechanism? Honestly?
Steve Levitt
Maybe it's you, Dubner. Maybe it's hanging around with you and your great humanity has started to rub off on me.
Stephen Dubner
I doubt it. But I'll take credit for it. That was our 2019 episode, Abortion and Crime Revisited. We will be back very soon with a new episode of Freakonomics Radio. Until then, take care of yourself. And if you can, someone else too. Freakonomics Radio is produced by Stitcher and Renbud Radio. You can find our entire archive on any podcast app, also@freakonomics.com where we publish transcripts and show notes. This episode was produced by Zach Lipinski and updated by Teo Jacobs. Our staff also includes Dalvin Abuaji, Alina Cullman, Augusta Chapman, Eleanor Osborne, Ellen Frankman, Elsa Hernandez, Gabriel Roth, Greg Rippon, Jasmine Klinger, Jeremy Johnston, John Schnarz, Lyork Bowditch, Morgan Levy, Neal Carruth, Rebecca Lee Douglas, and Sarah Lilly. Our theme song is Mr. Fortune by the Hitchhikers. Our composer is Luis Guerra. As always, thank you for listening.
Steve Levitt
I'm frenetic from the morning, so I have to slow myself down. I'm on some like other planet.
John Donohue
The Freakinom Comics Radio Network. The Hidden side of Everything.
Steve Levitt
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Freakonomics Radio: "Abortion and Crime, Revisited (Update)" - Detailed Summary
Release Date: October 28, 2024
Host: Stephen J. Dubner
Guest Experts: Steve Levitt, John Donohue, Jessica Walpole Reyes
In this compelling episode of Freakonomics Radio, host Stephen Dubner revisits a provocative and influential hypothesis first introduced in the Freakonomics book: the potential link between legalized abortion and the subsequent decline in crime rates in the United States. This revisit incorporates updated data and addresses past critiques, offering a comprehensive exploration of the theory's evolution and its implications in the current socio-political landscape.
Two years after the U.S. Supreme Court's landmark decision to overturn Roe v. Wade, Stephen Dubner reflects on the shifting abortion laws across states and their broader societal consequences. He introduces listeners to a hypothesis initially proposed by economists Steve Levitt and John Donohue: legalized abortion may have played a significant role in reducing crime rates approximately two decades later.
Steve Levitt explains, "I was spending most of my waking hours trying to figure out this puzzle about why was it the crime, after rising for 30 years from 1960 to 1990, had suddenly reversed?" (00:03-06:28). This curiosity led Levitt and Donohue to explore unconventional factors beyond conventional explanations like policing, economy, and drug epidemics.
After publishing their 2001 paper, "Impact of Legalized Abortion on Crime," Levitt and Donohue faced intense scrutiny and backlash. Critics from both pro-life and pro-choice camps attacked the study, accusing it of endorsing controversial views on abortion and inadvertently touching on eugenics.
Steve Levitt recounts the personal toll: "Everybody hated it... The number of death threats that I got from the left was actually greater than the number of death threats I got from the right." (21:36-22:32).
A significant critique arose from economists Christopher Foote and Christopher Getz, who identified a coding error in the original study. Levitt admits, "We had made those mistakes... but the hypothesis, I think, comes through in flying colors." (25:12-27:20). Although the error weakened some results, subsequent corrections reinforced the original hypothesis, highlighting the robustness of their findings despite initial methodological flaws.
In the updated analysis, Levitt and Donohue re-examined their original hypothesis using data extending to 2014. The new findings revealed an even stronger correlation between legalized abortion and crime reduction. Steve Levitt states, "The states that had high abortion rates over that period... have crime rates that have fallen about 60% more than the states that had lowest abortion rates." (37:23-37:48).
Jessica Walpole Reyes, an economist specializing in environmental toxicants and social behavior, contributed to the discussion by introducing the impact of lead pollution on crime rates. Her research suggested that both legalized abortion and the removal of lead from gasoline independently contributed to the decline in crime, emphasizing the multifaceted nature of societal changes.
Reyes' research adds another layer to the understanding of crime reduction. John Donohue explains, "I include their abortion measure in my analysis, and I find that the abortion effect is pretty much unchanged when one includes the lead effect..." (32:10-32:17). This suggests that multiple factors, including both abortion policy and environmental changes, played significant roles in shaping crime trends.
The intersection of abortion and crime remains a highly contentious and emotionally charged topic. The original study's implications sparked heated debates, often overshadowing the empirical evidence with ideological stances. Steve Levitt reflects on the public's misunderstanding: "We really lost the media battle because we looked stupid, because we had made the mistake." (27:36-27:42). Despite methodological challenges, the updated study underscores the importance of nuanced, data-driven discussions over polarized narratives.
The episode also touches on Supreme Court Justice Clarence Thomas' controversial remarks linking abortion to eugenics, highlighting the persistent misinterpretations and politicization of the research.
Levitt and Donohue discuss the broader policy implications of their findings. Steve Levitt suggests a reconsideration of aggressive policing and incarceration policies, proposing instead a focus on creating environments where children are wanted and nurtured. "If unwantedness is such a powerful influencer on people's lives, then we should try to do things to make sure that children are wanted." (43:32-44:08).
Jessica Walpole Reyes emphasizes preventative measures: "A country like the Netherlands... has much, much lower rates of abortion... because they have really tried to reduce unwanted pregnancies." (40:21-41:10). This indicates a potential shift towards policies that support family planning and parental resources as means to foster societal well-being and reduce crime.
The episode delves into the personal transformations experienced by the researchers. Steve Levitt shares how the study impacted his approach to fatherhood: "When I first was having kids, I didn't feel maybe so obligated to make children feel loved... I'm just trying to make them feel incredibly loved." (50:30-52:45). This humanizes the often abstract discussions of policy and reinforces the study's underlying message about the profound effects of societal support on individual outcomes.
In "Abortion and Crime, Revisited (Update)," Freakonomics Radio offers a thorough and introspective examination of a groundbreaking and controversial hypothesis. By integrating updated data, addressing past critiques, and exploring additional factors, the episode underscores the complexity of societal trends and the necessity for multifaceted, evidence-based approaches to policy-making. It challenges listeners to look beyond surface-level narratives and consider the deeper, often hidden connections that shape our communities.
Notable Quotes:
Stephen Dubner (00:03): "The law of unintended consequences isn't really a law, but it is at least a principle that we talk about a lot on this show."
Steve Levitt (08:14): "I had the idea that maybe legalized abortion might have reduced crime."
Jessica Walpole Reyes (24:32): "You should be trying to figure out what is true."
Steve Levitt (43:32): "I think there are lots of moving parts to this story... if unwantedness is such a powerful influencer on people's lives, then we should try to do things to make sure that children are wanted."
Steve Levitt (51:11): "When I first was having kids, I didn't feel maybe so obligated to make children feel loved... I'm just trying to make them feel incredibly loved."
This episode serves as a testament to Freakonomics Radio's commitment to uncovering the hidden layers of societal issues, prompting listeners to engage with complex ideas through a lens of curiosity and rigorous analysis.