CHICAGO (CBS) — The city of Chicago’s new police oversight agency, known as COPA, has ruled that the 2015 police shooting of Quintonio LeGrier was unjustified.

But key facts that led to that conclusion were uncovered by CBS 2, just days after the shooting. So, what took so long?

CBS 2 Political Reporter Derrick Blakley takes a look.

19-year-old Quintonio LeGrier took a swing at a Chicago cop with a miniature bat, and the officer shot him dead. That is the story Officer Robert Rialmo told investigators after the shooting two years ago.

It’s a story that the Civilian Office of Police Accountability now calls unbelievable, in a report released earlier this week.

“They stated the obvious, that the officer involved is just not credible. In other words, he’s a liar,” LeGrier family attorney Basileios Foutris says.

Rialmo claimed LeGrier was 3 feet away when LeGrier took a swing, and Rialmo opened fire.

But COPA concludes “there is no credible evidence” that LeGrier ever swung the bat.

Just three days after the shooting, an eyewitness told Blakley, Rialmo was 30 feet from LeGrier when the officer opened fire from the sidewalk or parkway.

That is also COPA’s conclusion.

“The shell casings that were shot, they were found on the sidewalk area and near the street, which would suggest to me that the gunfire came from a substantial distance away, that no police officers’ life was in danger at the time,” attorney Sam Adam Jr. says.

Again, COPA reached the same conclusion, that “a reasonable officer would not believe he was in danger of death or great bodily harm.”

So, what took so long to sort this out? The attorney representing LeGrier’s family says the old police watchdog agency, known as IPRA, simply dragged its feet. Now, he’s demanding action.

“The superintendent should go to the police board asking for this man to be fired,” Foutris says.

That is a decision Chicago Police Supt. Eddie Johnson has 90 days to make, although the final decision rests with the police board.

Meantime, in light of the COPA report, Foutris says the city should move to settle the civil suit the LeGrier family has filed against police.

That suit is scheduled to go to trial next June.

Also killed in the incident was LeGrier’s neighbor, Bettie Jones, 55. The Chicago Police Department acknowledged early on that her fatal shooting was an accident.

The Chicago police union questions COPA’s findings and says they are politicized.