Serial killer Robert Pickton, shown here during his murder trial in 2006, was fatally assaulted at the Port-Cartier federal penitentiary in May 2024. (Jane Wolsack/The Canadian Press)An inmate who has pleaded guilty to murdering Robert Pickton in prison last year says he did it for the serial killer's victims. Martin Charest admitted on Thursday morning to fatally assaulting Pickton with a broken broom handle at the Port-Cartier federal penitentiary in May 2024. Charest pleaded guilty to first-degree murder during a court appearance in Sept-Îles, Que., northeast of Quebec City. Pickton was convicted in 2007 of six counts of second-degree murder,...