The weapon or object a person is holding can attract our attention so much that it impairs our memory for the person – especially when stereotypes mean we associate the object they’re holding more with a person of the opposite sex. So, a knife held by a woman impairs memory for the woman, a held knitting needle impairs memory of a man.
Crime, Hysteria and Belle Époque Hypnotism: The Path Traced by Jean-Martin Charcot and Georges Gilles de la Tourette. “Gilles de la Tourette’s strong and public interest in hypnotism nearly cost him his life, when a young woman who claimed to have been hypnotized against her will shot him in the head at his own home in 1893. It was subsequently shown that hypnotism had nothing to do with it.” [hat tip: mind hacks]
The moral psychology of indirect agency: “Acting indirectly through another can hide the fact that one has caused harm, hide the fact that one knowingly chose to cause harm, and hide the extent of one’s control over the harmful outcome”.