Federal prosecutors are asking a court to throw out their own criminal case against the former national security adviser Michael Flynn. We look at what led to that decision. Guest: Mark Mazzetti, a Washington investigative correspondent for The New York Times. For more information on today’s episode, visit nytimes.com/thedaily.  Background reading: Attorney General William Barr’s extraordinary decision to drop the criminal case against Mr. Flynn shocked legal experts, won President Trump’s praise and prompted a career prosecutor to quit the caseThe federal judge overseeing the case has appointed a hard-charging former prosecutor and judge to oppose the Justice Department’s efforts. The dropped charges against Mr. Flynn granted him another turnabout in a life filled with them.