Chicago Police Department's newest class of recruits take their Oath of Office during their graduation ceremony in Chicago, Illinois, April 21, 2014. REUTERS/Jim Young A deal between the City of Chicago and its embattled police unions have made it extraordinarily easy for police to file false reports after shootings, a panel assigned by Chicago Mayor Rahm Emanuel found.

The details were revealed Wednesday in a scathing report on longstanding systemic racism within the Chicago Police Department.

According to the report, the city's collective bargaining agreements allow Chicago police officers to wait 24 hours after a shooting to provide a statement, giving them time to confer with other officers and get their story straight.

That's what the panel suggests happened following the 2014 death of Laquan McDonald, a black teenager whose fatal shooting by police ignited a firestorm of protest and debate.

The day after the shooting, the Chicago Police Department put out a statement saying McDonald, who was holding a 3-inch knife, had posed “a very serious threat to the officers" and that he “refused to comply with orders to drop the knife and continued to approach the officers.”

Several officers who were on the scene, including Jason Van Dyke, the officer who shot McDonald, repeated that account in their subsequent statements.

Combination of still images from video released by Chicago Police show Laquan McDonald walking and subsequently shot in Chicago Thomson Reuters Dashcam footage of the incident that was released the following year showed McDonald veering away from the officers at the time he was shot, seemingly contradicting the officers' accounts.

"Initial reports of the shooting were superficial and false," the panel's report states.

"The truth is that at the time Van Dyke fired the first of 16 shots, Laquan McDonald posed no immediate threat to anyone."

Demonstrators block the street during protests in Chicago following the release of a police video of the 2014 shooting of a black teenager, Laquan McDonald, by a white policeman, November 24, 2015. REUTERS/Jim Young The 24-hour grace period isn't the only agreement that works to officers' advantage. According to the panel's report, Chicago police can amend statements after viewing video or audio evidence.

And not only are anonymous complaints against officers prohibited, accused officers must be given the names of people who filed complaints against them, the report found.

All these provisions "have essentially turned the code of silence into official policy," the report reads.

The police department can increase accountability and rebuild public trust by changing these provisions, the report recommended.

Read the full report here.