William Balfour, the 27-year-old convicted felon suspected in the murders of Jennifer Hudson‘s mother, brother Jason and nephew Julian, refuses to take a lie detector test, but insists he’s innocent. Balfour is the estranged husband of Jennifer’s older sister Julia, and once lived in the home where the murders took place but was kicked out last winter. A gun was found Wednesday in a vacant lot near where Julian’s body was discovered in an SUV. The seven-year-old had been shot twice in the head. The weapon has been sent to a crime lab for testing. Balfour, who served seven years for attempted murder and carjacking, was released on parole in 2006. He was taken into custody after the Hudson murders and is being held as a “person of interest.” It’s come to light that he missed several conditions of his parole — required anger management counseling and substance abuse courses. Records show that Balfour was arrested with cocaine in his car last June, but authorities overlooked the incident rather than return him to prison on a parole violation. Balfour’s father is currently serving a 30-year prison sentence for murder. His brother served time for drug dealing. His mother, Michele, claims her son is innocent.