The 28-year-old Missouri police officer who killed unarmed black teen Michael Brown in August, sparking months of protests in the city of Ferguson, will likely never be a law enforcement officer again, his lawyer said in an interview with NBC station KSDK on Thursday.

Darren Wilson has decided to never return to policing, attorney Neil Bruntrager said. Currently, the officer is in discussions with the Ferguson, Missouri, police department on the terms and conditions of his departure.

"Realistically speaking, Darren will never be a police officer again, and he understands that," said Jim Towey, another one of his attorneys. "Going forward it will be school, and trying to carve out a new niche, new career, for he and his family."

"There's no way in the world he can go back to being a police officer. It's not a question of if, it's a question of when."

On Monday night, chaos and unrest returned to the streets of Ferguson after the grand jury announced its verdict to not indict Wilson, with thousands of enraged protesters coming out and setting fire to dozens of buildings and cars, looting businesses in the area where the unarmed, black 18-year-old was fatally shot, while police responded with tear gas and flash-bang canisters, Breitbart reported.

Hundreds of gunshots were reportedly heard by authorities, which for some time prevented fire crews from responding to emergency scenes and fighting the flames.

About 61 people were arrested overnight on charges ranging from unlawful assembly to arson to trespassing and burglary, St. Louis County Police spokesman Brian Schellman said.

In an ABC interview this week, Wilson claimed to have a "clean conscience," insisting "I did my job right" when he fatally shot the teen, who he claimed had tried to grab his gun and then charged at him that day.

But some other witnesses have claimed that the unarmed teen had his hands up when he was fatally shot.

In the aftermath of the shooting, Wilson has received death threats, Bruntrager said. Given the outrage over the case, Wilson's lawyers expressed that the Ferguson officer could simply not go back to work. 

Meanwhile, U.S. Attorney General Eric Holder announced on Tuesday that the federal investigation into the shooting of Brown will be continued by the Department of Justice and the FBI, Breitbart reported.

The FBI and the Justice Department will pursue two investigations, one into potential civil rights violations by the 28-year-old cop when he fatally shot 18-year-old unarmed Brown on Aug. 9, and one into the practices of the overwhelmingly white Ferguson police force, which operates in a predominantly black community.