The singer and actress, 30, is on the witness list and, once testimony begins, is expected to appear regularly at the trial of William Balfour, her former brother-in-law, which begins Monday in Chicago with jury selection, CNN reports.
Balfour was estranged from wife Julia – Jennifer’s sister – at the time of the killings. He is charged with fatally shooting Hudson’s brother Jason, her mother Darnell Donerson, and Julia’s 7-year-old son Julian King, allegedly in a jealous rage over what he thought was another man in Julia’s life.
Balfour has pleaded not guilty, and his lawyer has said there is no forensic evidence tying him to the murders.
Hudson, who won an Oscar for Dreamgirls in 2006, has not often discussed the murders. She first spoke up publicly to VH1 in 2010, saying the tragedy “was surreal It was like I was outside of myself.”
She added: “I’d pray when I get up in the morning, and pray before I lay down at night. If I didn’t, I’d wake up depressed.”