(CNN) — Nearly five years after a black teenager was shot and killed by Chicago police, new evidence could help his mom get closer to learning the truth about the circumstances surrounding his death.

This week, US District Court Judge Jorge L. Alonso of Chicago ruled to reopen discovery in the federal wrongful death lawsuit of Roshad McIntosh, according to court records.

McIntosh was 19 years old when he was shot and killed by a Chicago police officer in August, 2014.

An investigation of his death by Chicago’s Independent Police Review Authority (IPRA), which is now called COPA, found his shooting was straightforward. An officer said McIntosh pointed a gun at him. The officer fired three shots, killing McIntosh. The review authority found the shooting to be justified or “within policy,” and the case was closed by the agency in October 2015.

The review authority did not recommend any disciplinary action against any officer involved, and the Cook County State Attorney did not file criminal charges.

McIntosh’s mother, Cynthia Lane, filed a wrongful death lawsuit in federal court against the City of Chicago and some of the officers involved in 2015, claiming McIntosh was unarmed at the time he was shot. Attorney Sarah Gelsomino said witnesses have claimed police planted a gun on McIntosh after the fatal shooting.

“We’ve never believed the narrative given by the police in this case,” said Andrew Stroth, Lane’s attorney.

CNN followed Lane’s quest to find answers for her son’s death as she requested her son’s hospital records from the day of the shooting and obtained paramedic’s reports. It’s all documented in a three-episode CNN digital documentary titled “Beneath The Skin,” which raised serious questions about the original investigation.

COPA reopened its investigation into McIntosh’s killing in August 2017. The case remains open.

And now the evidence gathered during the re-investigation has become the catalyst to reopen discovery in the federal case.

“Based upon the additional and supplemental disclosures made from March 22, 2019 to the present by the City of Chicago relating to the reopened investigation by COPA of the underlying incident at issue in this case, the parties agree that it is appropriate to reopen discovery for the limited purpose of exploring the COPA re-investigation,” the parties wrote in a joint status report filed with the court.

The City of Chicago declined to comment, citing pending litigation. When contacted by CNN, the Fraternal Order of Police Chicago Lodge 7 did not comment on the case.

“This is all about getting to the truth for Cynthia Lane,” Stroth said. “This new information is going to support our theory that Roshad McIntosh was unjustifiably and unconstitutionally shot and killed by Chicago police.”

According to Stroth, the reopening of discovery gives his team access to all the documents, data, transcripts and exhibits generated by COPA’S re-investigation. It also allows him to interview witnesses who were questioned by COPA.

“It makes me more confident in getting justice and that’s what I’ve wanted from the beginning,” Lane said.

Judge Alonso set the discovery deadline for September 30, 2019, according to court documents which also note that the deadline could be extended.

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