Richard A. Oppel Jr.

"Among the six deadliest mass shootings in the last six years, the only one not carried out with an AR-15 style rifle was the Orlando nightclub attack two years ago that left 49 dead. The gunman, Omar …"

"Newtown. San Bernardino. Las Vegas. Sutherland Springs. And now, Parkland. Five of the six deadliest mass shootings of the past six years in the United States. In each of them, the gunman had an AR-15…"

"The N.R.A. calls the AR-15 the most popular rifle in America. The carnage in Florida on Wednesday that left at least 17 dead seemed to confirm that the rifle and its variants have also become the weap…"

"A vast majority of guns used in 19 recent mass shootings were bought legally and with a federal background check. At least nine gunmen had criminal histories or documented mental health problems that …"