Thursday, February 23, 2023

Not the Story I Was Looking For But Unsurprising

 1/24/23 NPR:

Three shootings with multiple victims shook California over the last few days. The shootings Monday at two farms in Half Moon Bay, Calif., closely followed a massacre over the weekend at a dance hall in Monterey Park, Calif.

That's no surprise, say scientists who study mass shootings. Research shows that these incidents usually occur in clusters and tend to be contagious. Intensive media coverage seems to drive the contagion, the researchers say.

Back in 2014 and 2015, researchers at Arizona State University analyzed data on cases of mass violence. They included USA Today's data on mass killings (defined as four or more people killed using any means, including guns) from 2006 to 2013, data on school shootings between 1998 and 2013, and mass shootings (defined as incidents in which three people were shot, not necessarily killed) between 2005 and 2013 collected by the Brady Campaign to Prevent Gun Violence.

The lead researcher, Sherry Towers, a faculty research associate at Arizona State University, had spent most of her career modeling the spread of infectious diseases — like Ebola, influenza and sexually transmitted diseases. She wanted to know whether cases of mass violence spread contagiously, like in a disease outbreak....

"What we found was that for the mass killings — so these are high-profile mass killings where there's at least four people killed — there was significant evidence of contagion," says Towers. "We also found significant evidence of contagion in the school shootings."

In other words, school shootings and other shootings with four or more deaths spread like a contagion — each shooting tends to spark more shootings.

"So one happens and you see another few happen right after that," says Jillian Peterson, a criminologist at Hamline University in Minnesota and founder of the nonpartisan think tank, The Violence Project. She wasn't involved in the Arizona State research but has found similar patterns in her own research.

Towers and her colleagues also found that what set apart shootings that were contagious was the amount of media coverage they received. "In the incidences where there were four or more people killed, and even school shootings, those tended to get national and even international media attention," says Towers.

Can we ban "assault media"?  Obviously not.


  1. Should we even if we could? Suppressing the copycat effect could be valuable. But OTOH, denying the public information that could alert them to possible dangers could be harmful.

    I saw a comment recently about the level of gang violence in Sweden, with numerous shootings and bombings that somehow never make the news. That's because nearly all the perpetrators - and most of the victims - are Moslem immigrants.) The Powers That Be in that country suppress anything that would "fuel bigotry"

    1. I thought ethnically directed violence was evidence of bigotry.

  2. I read about this theory some years back, and there was evidence for the thesis even then. This hasn't been a secret to Leftists. We can only conclude that the media gives the intensive coverage to the various mass murders and shootings in the hopes that people who would copy them are induced to actually do so.