Rep. Claudia Tenney, R-Utica, was speaking with a radio host from Albany, N.Y., about how to prevent future mass shootings when she made the claim.
“It’s interesting that so many of these people that commit the mass murders end up being Democrats, but the media doesn’t talk about that either,” Tenney said on Feb. 21, 2018.

…”Most of the school shooters are children who wouldn’t know a conservative from a communist,” said Jack Levin, Northeastern professor and co-director of the Brudnick Center on Violence and Conflict. “The idea of associating politics with these mass murders is absurd. It has absolutely nothing to do with it.”
Lipman agreed: “There is absolutely no evidence to show that mass killings are motivated by political ideologies of any type. All of the mass killings we’ve seen have been motivated by a lethal combination of a small subgroup of mental illnesses, and easy accessibility to weapons of mass killing during the peak symptomatology of those illnesses.”
Do many mass shooters ‘end up being Democrats’, as Rep. Tenney said? No | PolitiFact New York
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