CHICAGO (CBS) — A second video from a squad car dashboard camera, showing another fatal shooting by a Chicago police officer, will be released, Mayor Emanuel said Thursday.

“We will do that next week,” the mayor told reporters.

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The video captures a Chicago police officer shooting Ronald Johnson, about a week before the fatal shooting of Laquan McDonald in October, 2014.

The release of the McDonald video sparked protests, demanding justice for McDonald–who was shot 16 times–and the resignations of top city officials. The officer in the McDonald shooting, Jason Van Dyke, has been charged with first-degree murder. Police Supt. Garry McCarthy was fired in the aftermath of the protests.

Earlier this week, Michael Oppenheimer, the attorney for the Johnson family blasted the city for what he calls a year-long cover-up.

“They are still seeking to hide this video,” Oppenheimer said. “They are still denying justice for Ronnie and his family.”

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Johnson’s family contends the dash cam video proves Johnson did not aim a gun a police officers during a foot chase in October 2014. That’s the justification Officer George Hernandez gave for firing the shots into Johnson’s back that killed him. Johnson’s mother and his attorney have seen the video.

“I am 100 percent certain that Ronald Johnson had nothing in his hands when he was running,” Oppenheimer said.

According to the Cook County Medical Examiner, Johnson was shot in the shoulder and leg.

Meantime, Alvarez earlier this week said she’s not opposed to release of that video and revealed for the first time she’s investigating possible criminal charges against Officer Hernandez. That comes as a complete surprise to Johnson’s attorney.

“There has been no state’s attorney investigation,” Oppenheimer said. “Every main witness in this case has indicated they have not been contacted at all by anyone from the state’s attorney’s office.”

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Police have said Johnson pulled a gun during a chase in the 5400 block of South King Drive, after officers responded to a call of shots fired one block away.