Who exactly joined the mob that, almost a year ago, on Jan. 6, breached the walls of the U.S. Capitol in a bid to halt the certification of President Biden’s election victory? Members of far-right extremist groups were present but so too were also doctors, lawyers, substitute teachers and church deacons, many of whom had previously been nonpolitical. The question of why they were at the Capitol that day is hard to answer, but some of the most useful clues come from three F.B.I. interviews that have been released to the public. Today, in the first of a three-part look at what happened on Jan. 6 and what it tells us about the state of American democracy, using voice actors, we bring one of those interviews to life — that of Robert Reeder, a father and delivery driver from suburban Maryland.