In a stunning reversal on Thursday, Chicago Mayor Rahm Emanuel buckled and said he no longer opposes releasing video of another controversial police shooting.

Emanuel’s administration has been fighting the release of police video showing the shooting of Ronald Johnson, a 25-year old killed in October 2014. The battle not only echoes the dispute over video of indicted officer Jason Van Dyke shooting 17-year-old Laquan McDonald, but is clearly impacted by it, with mounting pressure on Emanuel, police and Chicago’s top prosecutor.

Emanuel’s reversal is striking because he spent a year opposing the release of video showing McDonald’s death, insisting such footage compromise fair investigations.

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Michael Oppenheimer, the lawyer for Johnson’s family, said the video shows him unarmed, “running full speed away from” officer George Hernandez, who then “takes out his weapon, he aims, points, and he fires five shots.”

In a new interview with MSNBC, Oppenheimer said he’s personally watched the video “many times.” He is under court order not to release it. His civil suit for the family alleges that after shooting Johnson, police planted a weapon on him, which they deny.

In another fast-moving development this week, Chicago prosecutor Anita Alvarez announced a criminal inquiry into the Johnson shooting.

It was her first announcement of such an inquiry, even though the incident occurred over a year ago. Oppenheimer said Alvarez’s sudden announcement of an investigation is “disingenuous.”

“I don’t know if I believe it,” he said, when asked about her new announcement. “That video was available 14 months ago,” he said, “if they thought they saw a video showing Ronald Johnson carrying a weapon, why didn’t they release it then?” he asked.

Oppenheimer, who once worked as a prosecutor in the Cook County attorney’s office — which Alvarez now leads — also argued her inquiry clearly isn’t serious because none of the key witnesses have even been interviewed.

“No one from the states attorney’s office,” he said, has contacted “the witnesses in this case, civilian and police officers.”

“I know that they have not interviewed George Hernandez,” Oppenheimer added, saying Hernandez’s only legal interview about the case came in the six-hour deposition he conducted for the civil case.

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Johnson’s mother, Dorothy Holmes, told MSNBC she believes that even after Emanuel fired the head of Chicago police, more reform is needed because corrupt officers are “still in office” and there is “still a cover-up” of police misconduct. She argued that “cover-up” will unravel once the public sees the video of police shooting her son.

After the incident, Chicago police said Johnson had a gun and “pointed his weapon in the direction of the pursuing officers,” then “as a result of this action, an officer discharged his weapon,” killing Johnson. That police account also states “a weapon was recovered.”

Oppenheimer alleges that weapon was actually planted to frame Johnson. He said there are both civilian and police witnesses, present that night, who will testify Johnson was unarmed. The Chicago Police Department denies that cover-up, insisting Johnson was armed.

Oppenheimer also argued that it would not be logical for police to find a gun in Johnson’s hand after he was shot down. “He was unarmed,” Oppenheimer said. “There was no way anything could have stayed in his hand while he had been shot, running full speed.”

Johnson does not have any gun charges or felonies on his criminal record, according to criminal files provided by the Cook County clerk to MSNBC. He was charged with gambling in 2007, pled guilty to misdemeanor assault in 2008, and pled guilty to gang loitering in 2011. Legally, a suspect’s past criminal record is not relevant to allegations of excessive force against an officer.

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While the Johnson family’s civil suit is pending against the police, Oppenheimer says the city has not offered a settlement.

The family’s civil case includes claims of excessive force and wrongful death, and beyond the actions of any single officer, it also alleges Chicago Police “attempted to cover up” the shooting by distributing “false” statements about the killing, all in a coordinated effort with Chicago Police Union spokesman Pat Camden.

The suit calls it a “code of silence.”

Oppenheimer is also leading the freedom of information suit urging the video’s release — the next hearing is Thursday, though Oppenheimer said it could come out even before the hearing now that Emanuel is supporting the video’s release.

Ultimately, Holmes said her hopes for the effort go far beyond getting compensation from the city. “Money is not the issue,” she told MSNBC. “My son’s life didn’t have a price tag on it.”