CHICAGO (CBS) — A group of civil rights attorneys, elected officials, and civil rights activists has filed a petition asking a judge to appoint a special prosecutor to take over the Laquan McDonald murder case, claiming Cook County State’s Attorney Anita Alvarez can’t be trusted to oversee the matter.

Their petition also asks for a special prosecutor to look into a possible police cover-up of the October 2014 shooting, in which Officer Jason Van Dyke shot McDonald 16 times as the teenager was walking away from police.

Cook County Commissioner Chuy Garcia said the public has lost confidence in Alvarez after she took more than a year to charge Van Dyke with murder.

Sheila Bedi, an attorney with the MacArthur Justice Center, said Alvarez is too closely allied with the Fraternal Order of Police to handle the case fairly, and should be disqualified from representing the state in the McDonald case.

“Anita Alvarez is beholden to the police union. Her failure, over and over again, in many other cases, to appropriately and timely charge police officers who have committed crimes, even in the face of overwhelming evidence – indisputable evidence – makes clear that she has helped to facilitate the code of silence that so pervades the Chicago Police Department,” she said.

Also supporting the push for a special prosecutor were U.S. Rep. Danny Davis, the City Council’s Black Caucus, and a number of attorneys who have handled police misconduct lawsuits against the Chicago Police Department.

They all said Alvarez can’t be trusted to fairly prosecute Van Dyke, and handle an investigation of possible wrongdoing by other officers who were at the scene, and backed up Van Dyke’s claims McDonald lunged at officers with a knife – even though dashcam video of the shooting shows McDonald was walking away from police when he was shot.

“If there is to be justice, then this is a necessary part of it,” Davis said.

Alvarez has repeatedly defended her handling of the McDonald case, saying she was working alongside the FBI and federal prosecutors to thoroughly investigate the shooting and build a “meticulous case” against Van Dyke.

“It is clear that there is no legal conflict in this case, and prosecution will proceed to hold Jason Van Dyke accountable for the murder of Laquan McDonald,” Alvarez said in a written statement Tuesday afternoon.

Many of the politicians and activists who were calling for a special prosecutor have thrown their support behind one of Alvarez’s leading challenger in the March primary, Kim Foxx.

“It’s more than a little coincidental that this action is being taken less than 30 days before an election, at a press conference held by the political supporters of a candidate for State’s Attorney,” Alvarez said.

Some in the group support Alvarez’ opponent Kim Foxx, including Alderman Howard Brookins Jr.

“I think the state’s attorney made it political,” Brookins Jr. said. “Anita Alvarez, even if she should lose the election next month, will still continue to be the state’s attorney until December.”

However, attorney Locke Bowman said he’s not trying to influence the race.

“This has nothing to do with Kim Foxx. It has nothing to do with the current political process that’s underway,” he said.

State’s attorney candidate Donna Moore also says she supports the call for a special prosuctor

The request will be heard by Criminal Court Presiding Judge Leroy Martin Jr. on Feb. 26.

Bowman and attorney Flint Taylor previously filed a successful petition to appoint a special prosecutor in the death of David Koschman. In that case, former U.S. attorney Dan Webb was appointed to investigate Koschman’s death at the hands of Richard “R.J.” Vanecko – a nephew of former mayor Richard M. Daley.

Chicago police had determined Koschman was the aggressor in a 2004 fight outside a Division Street bar, and Alvarez declined to press charges, saying there wasn’t enough evidence to sustain a case against Vanecko, but Webb won an indictment against Vanecko for involuntary manslaughter, and Vanecko later pleaded guilty and served 60 days in jail.

The presiding judge in the Van Dyke case will decide if a special prosecutor should be appointed.

“He could either do it on his own motion or he could hold a hearing, but it’s his decision,” said CBS 2 Legal Expert Irv Miller.