The guy responsible for that billboard (along the back side of the centerfield bleachers at Fenway Park), which changes its anti-gun message from time to time, is Boston developer John Rosenthal, founder along with Michael (son of Robert) Kennedy, of an organization named Stop Handgun Violence. Rosenthal was previously instrumental in a group named the American Hunters and Shooters Association, which pretended to be a pro-gun alternative to the NRA but was in fact an anti-gun organization from the get go.
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