(CNN) -- The U.S. Justice Department announced Tuesday that it will not pursue federal criminal civil rights charges against Michigan police officers who shot and killed a knife-wielding homeless man in July 2012.
Authorities said there was insufficient "evidence of willful misconduct" to warrant a federal criminal prosecution of the Saginaw Police Department officers who fired 46 bullets at Milton Hall, 49, during an argument. Hall was hit 11 times.
The incident occurred July 1, 2012, in a parking lot next to a shuttered Chinese restaurant, in full view of passing motorists. A video of the incident was obtained exclusively by CNN weeks later.
The Saginaw County prosecutor and the Michigan attorney general had declined to prosecute the officers.
"After a careful review of all of the evidence, experienced prosecutors from the Criminal Section of the Civil Rights Division and the United States Attorney's Office for the Eastern District of Michigan have determined that the evidence in this case is insufficient to prove, beyond a reasonable doubt, that the SPD officers willfully shot Hall for an unlawful purpose, rather than for their stated purpose of preventing Hall from harming SPD staff," the Justice Department said in a statement.
The statement continued: "Even if the officers were mistaken in their assessment of the threat posed by Hall, this would not establish that the officers acted willfully, or with an unlawful intent, when using deadly force against Hall."
Hall's family said he had a history of mental illness.
At the time of the shooting, then-Saginaw Police Chief Gerald Cliff said Hall was "known to be an assaultive person" with "a long history" of contacts with law enforcement, "not only with police from our department, but with the county."
In the video purchased by CNN, shot by a motorist from across the street, Hall was seen arguing with a half dozen officers. For more than three minutes he walks back and forth, and at one time appears to crouch in a "karate stance," according to the man who captured the scene.
Police said Hall had just had a run-in with a convenience store clerk. On the video, he tells police, "My name is Milton Hall, I just called 911. My name is Milton, and I'm p---ed off." When an officer tells him to put the knife down, he responds, "I ain't putting s--t down." He appears unimpressed by a police dog, telling officers, "Let him go. Let the motherf---ing dog go."
Finally, Hall turns to the left of the frame, where another officer had moved out of view a short time earlier. That's when the police open fire with a reported 46 shots in a five-second hail of bullets.
The on-site police supervisor was demoted to patrolman, police said afterward. Two others were disciplined for violating department policies in connection with the shooting. Three of their five dash-cam video cameras were not working properly.
In a statement, Jewel Hall, Milton's mother, said she was not surprised by Tuesday's development.
"However, that decision does not negate the civil litigation that we can pursue and the standards in that matter are less stringent and we believe justice will prevail."
The family filed a wrongful death lawsuit last year against the police department and the officers involved in the shooting after conducting its own investigation and consulting two nationally known experts in police practices, lawyers for the family said.