Jean McConville was ordered murdered by Sinn Fein’s Gerry Adams around 1972. She was a Catholic married to a Protestant but she helped an English soldier dying in the streets of Belfast. This upset Mr. Adams. He ordered the actor Stephen Rae’s wife (I forget her name) to pick her up in a car for interrogation. Although a mother of many children, she was dragged out of her bathtub and winded up dead and buried on a beach. This wife turned on Adams when she was diagnosed with terminal cancer, I believe, and told of the murder. That was only a few years ago that she admitted it. Adams, of course, denies this.
I’ve read about her providing information to British authorities as well; I just don’t know enough of the facts (and I doubt most people do) to assume he’s guilty of anything.