Chicago • Protesters who have been calling for Chicago Mayor Rahm Emanuel's resignation also have another target: a much-criticized, quasi-independent agency that was created to investigate complaints against police officers but has rarely ruled against them.

The mayor's critics complain that his pledge to reform the Independent Police Review Authority (IPRA) is too limited because he seeks to improve an existing system rather than scrapping it and starting over.

In the outrage that erupted over the video showing an officer fatally shooting Laquan McDonald, Emanuel sacked his police chief and set up a task force to recommend changes. He also replaced the head of the authority known as IPRA.

Former IPRA investigator and supervisor Lorenzo Davis said he was fired this year after refusing to reverse his finding in one fatal police shooting that it was not justified.

The idea behind IPRA when it was set up in 2007 was for the agency to be wholly independent of police and the mayor's office as a way to weed out bad officers, but that never actually happened, Davis' lawyer, Torreya Hamilton, said Thursday.

"The goal became to exonerate the police officer and therefore the city," said Hamilton, who represents Davis in a lawsuit he filed against the city over his firing.

Suspicion about reforms initiated by City Hall runs deep in Chicago, especially among blacks, who have heard similar pledges every couple of years, whenever allegations of police brutality arose. Many put more hope in a just-launched federal civil-rights investigation, though that could take years to play out.

In an address to the City Council this week, a sometimes emotional and sometimes tough-talking Emanuel apologized for any mishandling of the McDonald case and repeatedly pledged to improve how IPRA deals with the issue of police misconduct.

"Each time when we confronted it in the past, Chicago only went far enough to clear our consciences so we could move on," he said. "This time will and must be different."

In all, Lorenzo, himself a former Chicago police officer, was told six times to change his findings in favor of officers, according to Hamilton.

"There was never ever a time when they said, 'You want to exonerate an officer, and we think he should be disciplined,'" she said.

An IPRA spokesman declined to comment Thursday.

When it was created, the authority's exact operations were not made precisely clear. Many details were left to politically appointed administrators with law enforcement backgrounds. Since around 2008, when Davis began working there, more than 10,000 excessive-force complaints have resulted in the dismissal of just four officers, he said.

The authority's new head is Sharon Fairley, a recent federal prosecutor. Davis complains that Emanuel sought no feedback from the community before the appointment. He said IPRA should be led by someone not beholden to the established power structures and who can absorb and implement new procedures.

One activist on the Urban League panel, Trina Reynolds, argued that the agency is beyond salvaging, calling it "illegitimate."

Others expressed skepticism about Emanuel's newly created policing task force.

It includes several figures associated with existing accountability bodies, including Lori Lightfoot, a former assistant U.S. attorney who heads the Chicago Police Board, which is responsible for disciplining officers. Protesters attended one of its meetings Wednesday, demanding the resignation of its members.

Advocates are also seeking other reforms that include:

• Creating a new civilian-controlled body, the Police Auditor's Office. It would have subpoena and other powers to oversee police and IPRA, including unfettered access to all police records. Proponents say its head should not be chosen by the mayor but by a third party after feedback from the community.

• Renegotiating the city's union contract to strip it of provisions critics say can shield bad officers. Chicago-based lawyer Paul Strauss says one rule bars internal investigators from interviewing officers involved in shootings for 24 hours, potentially giving them time to coordinate fabricated stories.