Nicholas Johnson was mentioned in a PolitiFact Wisconsin piece about the 2nd Amendment and semiautomatic weapons.
Semiautomatics — which reload automatically but fire only once each time the trigger is depressed — are not banned, though some states do impose restrictions on them.
To check Ryan’s claim, we spoke with four law professors who are experts on gun law: Vladeck; Nicholas Johnson of Fordham University; Robert Spitzer of State University of New York-Cortland; and Adam Winkler at UCLA in Los Angeles. We also spoke to Adam Bates, a criminal justice policy analyst at the libertarian Cato Institute.