Police have charged the estranged brother-in-law of Jennifer Hudson with three counts first degree murder in the shooting deaths of the entertainer's mother, brother and young nephew.

Cook County state's attorney's office spokeswoman Tandra Simonton says prosecutors handed down formal charges against William Balfour on Tuesday in the deaths of Hudson's mother, brother and 7-year-old nephew.

Balfour had been in custody on a parole violation since the bodies of Hudson's mother, Darnell Hudson Donerson, and brother, Jason Hudson, were discovered in their home on the South Side of Chicago on Oct. 24. The body of Hudson's nephew, 7-year-old Julian King, was found three days later in a sport utility vehicle on the West Side. All three had been shot.

Balfour was arrested Monday at Stateville Correctional Center and released to detectives as he awaited formal charges in the shooting deaths of the singer and Oscar-winning actress' relatives, said Chicago police spokeswoman Monique Bond.

Prior to his arrest, police had identified Balfour, 27, only as a "person of interest" in the investigation.

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Police took Balfour into custody the same day the bodies of Donerson and Hudson were discovered. After 48 hours — the longest Chicago police can hold a person without charges — Balfour was taken by the Illinois Department of Corrections on the suspected parole violation.

Balfour — Julian's stepfather and the estranged husband of Jennifer Hudson's older sister, Julia Hudson — served seven years for a 1999 attempted murder and vehicular hijacking conviction.

His mother, Michelle Davis-Balfour of Chicago, told reporters outside a police station Monday night that authorities do not have a case against her son.

"If they found gun powder on his hands, you got a case; if they found a gun on him, he had a case; if they found a fingerprint on the truck that he did this, you got a case; but they don't have nothing," Davis-Balfour said.

Balfour had refused to take a lie-detector test and stopped cooperating with detectives in the case, a police official, who was not authorized to discuss the case publicly and spoke on condition of anonymity, has said.

Police have confirmed they found the gun used in the killings. The .45-caliber gun was discovered Oct. 29 in a vacant lot in the West Side neighborhood where the King's body was found a few days earlier.

Bond declined to discuss any evidence Monday. But after a hearing at the prison, the chairman of the Illinois Prisoner Review Board said a woman had told authorities that a gun used in the slayings was "identical" to the gun that was recovered.

At the time, board Chairman Jorge Montes said the evidence was key to a decision finding probable cause that Balfour violated his parole and should remain locked up pending a Dec. 3 hearing before a review board panel.

Balfour did not have an attorney at the November hearing, and the Cook County public defender's office said at the time that nobody from the office had been assigned because he was not formally charged with a crime.

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