Mary Lou McFate was a gun-control activist who served on the boards of two anti-violence groups. But she is also accused of working as a paid spy for the National Rifle Association. McFate also had another incident as a spy. The 62-year-old from Sarasota, Fla., infiltrated an animal-rights group in the late 1980s at the request of a company and befriended an activist who was later convicted in a pipe-bomb attack against the medical-supply business, the company acknowledged in news reports at the time.General Opiniongun controlOpinion