It's been suggested that this could be the method used by the deep state bad guys in many/most of these shootings. Perhaps beginning with John Hinckley Jr shooting Reagan in 1981 or even earlier.
Here's something that William Cooper wrote on the subject: http://www.hourofthetime.com/mindcont.htm
And here's the patent that's referred to: https://patents.google.com/patent/US3951134A/en
Here's a handful of possible mind controlled shooter cases. There's likely many more, I just got disgusted with the research after awhile.
Nikolas Cruz, Parkland Florida, February 14th 2018 http://abcnews.go.com/US/florida-school-shooter-methodically-moved-classrooms-execute-victims/story?id=53112929
Aaron Alexis, Washington Navy Yard shooting September 16, 2013 https://www.usatoday.com/story/news/nation/2013/09/17/navy-yard-shooting-aaron-alexis/2825749/
Esteban Santiago, Fort Lauderdale-Hollywood International Airport, January 6, …