Last week, NPR’s Lulu Garcia-Navarro asked Joe Biden whether, if elected, he could envision Donald Trump being prosecuted. Biden replied that the prosecution of a former president would be a “very, very unusual thing” and probably “not very good for democracy.” The former vice president said he would not stand in the way if the Justice Department wanted to bring a case, but when Garcia-Navarro pressed him, he suggested she was trying to bait him into a version of Trump’s threat against his 2016 opponent: “Lock her up.”