CLEVELAND, Ohio -- Fired Cleveland police officer Timothy Loehmann, who fatally shot 12-year-old Tamir Rice, will begin fighting Wednesday to get his job back.

The embattled rookie police officer, fired not for shooting Tamir but for lying on his police application, will begin arbitration proceedings on Wednesday, according to four sources familiar with the proceedings.

The proceedings are expected to last three days and there is no set timetable for the arbitrator's decision. Arbitrators typically try to get decisions finalized within 60 days but can request an extension if both parties agree.

Loehmann's partner, Officer Frank Garmback, went to arbitration last month, the four sources said. The arbitrator who heard the case has not yet made his decision.

Garmback is fighting a 10-day suspension for his role in the incident. He was disciplined for driving his police cruiser and stopping in front of Tamir, putting Loehmann face-to-face with Tamir.

Calls and an email sent to Cleveland city spokesman Dan Williams were not immediately returned.

Cleveland police Det. Steve Loomis, who was the Cleveland Police Patrolmen's Association president when Loehmann was fired, previously said he believes that Loehmann will get his job back, despite being in his probationary period, which gave Cleveland Public Safety Director Michael McGrath more flexibility in letting him go.

He said Loehmann never intended to misrepresent himself on the application and simply ran out of space because the application gave him only so much room.

Loomis also previously said the firing was politically motivated, especially because Loehmann was cleared of any wrongdoing in the shooting by a county grand jury and a Cleveland police-commissioned review of the incident.

Tamir's mother, Samaria Rice, praised the city for firing Loehmann but said she wished it was because of the shooting, not for lying on his application.

Loehmann was a Cleveland police officer for less than eight months before the November 2014 shooting. He shot Tamir in less than three seconds after arriving at Cudell Recreation Center.

A disciplinary letter released in January 2016 specifically says that Loehmann lied about how his short stint at the Independence Police Department ended.

Loehmann was allowed to resign from the Independence department after six months following a series of incidents where supervisors determined he was unfit to be a police officer.

The disciplinary letter cites a letter in Loehmann's personnel file from Independence that says he was emotionally immature and had "an inability to emotionally function." The letter also cites an emotional breakdown Loehmann had on the gun range in Independence.

Cleveland officials said in the letter that Loehmann was supposed to disclose that information. He was also supposed to say in his application that he failed a 2009 written exam when applying to work as an officer in Maple Heights. Loehmann never mentioned the Maple Heights test.

Three officers -- a detective, sergeant and lieutenant-- in the police department's personnel unit, which conducts background checks on potential hires, were disciplined for failing to discover the circumstances surrounding his resignation from Independence police.

They also failed to find out that Loehmann failed a portion of his test to try and become a Cuyahoga County Sheriff deputy that showed he was mentally unfit for police work, according to the transcript of his disciplinary hearing. He also did not disclose that he failed his test for a position with Maple Heights police. He never put on his application that he even took the test in Maple Heights, which is a violation of the city policy.

The city paid a $6 million settlement to Tamir's family, which is likely the largest settlement the city has paid in a police-shooting case.

A review committee comprised of city officials that took the place of a normal internal affairs investigation, called the Critical Incident Response Committee, found that neither Loehmann nor Garmback violated any police policies.

They concluded that Garmback took a path towards Tamir that other officers regularly used, that he wasn't driving too fast and that he tried to stop sooner than he did, but skidded on the wet grass.

That put Loehmann in a position where he got out of the cruiser and was directly in line with Tamir. Dispatcher Constance Hollinger had told the officers that someone had a gun at the park, but failed to tell them the initial 911 caller said that it was "probably a juvenile" and that the gun was "probably fake."

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