CHICAGO (Reuters) - A Chicago agency that examines police misconduct will reopen an investigation into the fatal 2014 police shooting of a black teenager that led to demonstrations and a lawsuit, the group said on Thursday.

The Independent Police Review Authority determined in 2015 that the shooting of 19-year-old Roshad McIntosh - which police said occurred after he refused to drop a gun he pointed at an officer - was within department policy.

McIntosh’s family requested the case be reopened, the authority said. The family previously filed a federal court lawsuit alleging he was unarmed when police chased him into a yard and shot him as he tried to surrender.

“After a thorough review of the investigative file, we found sufficient reason to reopen the case for further investigation,” authority spokeswoman Mia Sissac said in a statement.

“A reopened case is not an indication that the findings will be modified, but only that further investigation is necessary,” Sissac added. She did not say what specific information led investigators to reopen the case.

Cynthia Lane, McIntosh’s mother, told Reuters on Thursday she wanted those involved with her son’s death to face charges. She said witnesses suggested her son was unarmed.

Chicago is working to enact reforms after a federal investigation in January found police routinely violated people’s civil rights. It cited excessive force and racially discriminatory conduct.

The U.S. Department of Justice report followed protests sparked by the autumn 2015 release of a video showing a white police officer fatally shooting black teen Laquan McDonald in October 2014.

McIntosh’s killing in August 2014 also ignited demonstrations and came just two weeks after the fatal police shooting in Ferguson, Missouri, of unarmed black teenager Michael Brown, which sparked violent clashes and put the issue of police use of force and race in the national spotlight.

A Chicago police spokesman did not immediately provide comment or say if the officer who shot McIntosh was still on the force. The Chicago police union declined to discuss the case.

The Cook County State’s Attorney Office, which earlier concluded there was no basis for criminal charges, said in a statement on Thursday that prosecutors would consider any new evidence that comes to light.

“In the event that IPRA’s reopened investigation produces material new evidence, we will reevaluate and determine whether such evidence impacts our decision as to potential criminal charges,” the statement said.