Mass shootings in the US since 1950 resulting in eight or more murders
By 
Note: These statistics don’t include the shooter or shooters if they were killed or committed suicide in the course of the incident (Not my choice: that’s just the way the statistics are presented in this source). They also don’t include one shooting from 1949, as the stats don’t cover the rest of that decade, or any previous period.
By decade
1950s: 0
1960s: 1 (University of Texas tower shooting)
1970s: 0
1980s: 6
1990s: 6
2000s: 7
2010s: 16 and counting
22 of these 36 mass shootings have taken place since 2007.
This is an update of an original post from almost exactly one year ago today. (It’s still unclear whether this morning’s mass murder was committed by a terrorist or a mentally ill white man).
Since then, this list has expanded by 12.5%.
Full disclosure: When after the latest carnage I went to update this list from memory, I remembered the Tree of Life Synagogue massacre that happened twelve days ago, but I didn’t recall the two mass shootings at high schools earlier this year, that together resulted in the murder of 22 students and five teachers. To be specific, I remembered the Stoneman Douglas shooting, but was under the impression it had taken place a couple of years ago, rather than in February. I didn’t remember the Santa Fe High School shooting at all (Only 10 people were murdered).
Update: The shooter was a 28-year-old white man, who was a veteran of one of our glorious ongoing wars. He also legally owned the weapon that he used to kill 13 people.
Investigators knocked on doors of surrounding residents to find out what they may know about Long. One neighbor who knew Long said he was a veteran who suffered from PTSD. She said, “I don’t know what he was doing with a gun.” Others said Long lived at the home with his mother.
Dean said Long was in the United States Marine Corps. The USMC released Long’s service record, detailing that he served from 2008 to 2013, deploying to Afghanistan from Nov. 16, 2010 to June 14, 2011. His ranking was a corporal as a machine gunner, the the USMC said.
Long had several interactions with the sheriff’s department over the years, Dean said. These incidents include a traffic collision, a traffic citation as well as an instance in which Long was a victim of battery at a local bar in 2015.
Dean also described an incident In April, when deputies were called to his Newbury Park home regarding a disturbance.
“He was somewhat irate, acting a little irrationally. They called out our crisis intervention team, our mental health specialist,” Dean said.
Those specialists ended up clearing him because they “didn’t feel he was qualified to be taken under 5150,” Dean said, referencing the California law code for the temporary involuntary psychiatric commitment of individuals who present a danger to themselves or others due to signs of mental illness.
His gun, which was a .45-caliber handgun, was purchased legally, Dean said. The Associated Press reports that he also deployed a smoke device. Dean said he has yet to confirm the use of such a device, though several witnesses alluded to it.