Everytown for Gun Safety’s Nick Suplina joins ABC News’ Linsey Davis to unpack what the Manhattan shooting tells us about the effectiveness of some of the strictest gun laws in the U.S.

Investigators discovered a second note at the Las Vegas home of the gunman who killed four people in midtown Manhattan, officials said. The note mirrors the one found on his body in New York, where he blamed football for his mental illness as authorities examine his brain for signs of CTE.