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On January 3 of this year, Timothy Glaze Dean was fatally shot by the Chicago police. Body-camera footage revealed he was armed with a knife at the moment of the incident.

A lawsuit filed on Wednesday by the lawyer representing his estate claims that Glaze Dean was shot 20 times. The attorney argues this shooting reflects a persistent pattern of excessive force by the CPD.

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The body-camera footage displayed officers leaving their car in response to a welfare check for Glaze Dean. A friend had raised concerns about his mental health, mentioning he was handling a knife. The video recorded police as they entered the Little Village apartment complex, rode the elevator to the sixth floor, and identified themselves at Glaze Dean’s door.

A second later, Glaze Dean walks into frame with a knife in his hand. Two seconds after that, as he walks towards police, they open fire, shooting 20 rounds.

READ MORE | Bodycam video shows CPD officers fatally shooting man apparently armed with knife in Little Village

Some bullets were fired after he was already on the ground without the knife and no longer a threat, according Glaze Dean family attorney Greg Kulis. The entire incident took less than two minutes from when officers exited their vehicle.

“The police don’t say, drop the knife. They don’t say, police, put your hands up, drop the knife, step back,” Kulis told the I-Team.

Kulis said the body camera footage showed a lack of any attempt by police to deescalate the situation and points to what he calls a broader problem with CPD of excessive use of force, referencing both Laquan McDonald and Dexter Reed, who were shot 16 and 13 times, respectively, by Chicago Police and were killed.

“I think it’s become a practice of policy to obliterate the threat and obliterate the source of the threat,” Kulis said.

Neither officer who opened fire has any previous misconduct allegations against them. ABC7 is not naming those officers because they have not been charged with a crime.

“You use that deadly force, but that doesn’t mean you can continue to use that deadly force when the threat is gone, because at that point, maybe somebody would have survived,” Kulis said.

“The officer responded to his training, and that was there’s lethal force coming toward him. He responded with lethal force,” ABC7 Police Affairs Consultant Bill Kushner said.

Kushner said given the circumstances, including the narrow hallway and no cover for officers as Glaze Dean advanced, they were left with no choice but to shoot. He said the common use of semi-automatic weapons by police can lead to multiple rapid fire shots.

“The officers did attempt to render aid. They did call for an ambulance. They applied tourniquets,” Kushner said.

“You feel for the families. You feel for police officers, but the city of Chicago has an obligation to make sure the officers go out there with the proper tools and the proper training,” Kulis said.

Both Kushner and Kulis said body-worn cameras are essential for police, and especially for public trust.

COPA said this is an ongoing investigation and Chicago police gave no comment.

There is a protest scheduled for Thursday, three months after Glaze Dean’s death.