CHICAGO (CBS) — Could Chicago’s former top cop be Mayor Rahm Emanuel’s first challenger for re-election?

According to the Illinois State Board of Elections, the “Garry McCarthy For Mayor” exploratory committee filed its official statement of organization on Wednesday. The committee did not immediately respond to a request for comment about McCarthy’s plans.

Forming an exploratory committee is just the first possible step in a run for mayor, and a long way from actual candidacy.

The move allows a potential candidate to raise money for a campaign, though McCarthy would still have to collect the signatures of 12,500 voters on nominating petitions to get on the ballot. He couldn’t start circulating petitions until about six months before the 2019 election.

So far, the McCarthy exploratory committee appears to be the only one established for the 2019 mayor’s race in Chicago.

Emanuel fired McCarthy as the city’s top cop in December 2015, a week after Police Officer Jason Van Dyke was charged with murder in the October 2014 shooting death of 17-year-old Laquan McDonald. Hours after Van Dyke was charged, the city released police dashboard camera video of Van Dyke shooting McDonald 16 times.

The high-profile shooting death of a black teenager by a white police officer sparked several days of protests across the city. Van Dyke is still awaiting trial.

Three months after he was fired, McCarthy said he had “nothing to do” with the McDonald scandal.

“They say, ‘Man, you got screwed, but somebody had to take the hit,’” McCarthy said. “I said, ‘You’re right’ and the person who is going to take the hit is going to be the person who committed the act and at the end of the day, police legitimacy in Chicago took an enormous hit and people are dying at record numbers right now as a result.”

After he was fired, McCarthy and his wife started a private security firm.

McCarthy also has criticized the U.S. Justice Department’s investigation of the Chicago Police Department.

The scathing report took the CPD to task for systemic violations of civil rights, finding officers regularly have used excessive force and discriminated against minorities. U.S. Attorney General Loretta Lynch said, during the investigation, the feds reached out to McCarthy for his input, but he was “not available.”

McCarthy called that “nonsense.”

“They must be really great investigators if they can’t find the former superintendent of police who lives right here in River North,” he said.

McCarthy said it’s odd that his perspective wasn’t included in the report. In fact, he says, he probably should have been the first person interviewed.

Weeks before the McDonald video was released, Emanuel said he was planning to run for a third term, but his approval ratings among African-Americans plummeted in the wake of the resulting scandal. In recent months, he has become more vocal about his support for immigrants’ rights, in an apparent bid to shore up support among Hispanic voters.

Cook County Commissioner Jesus “Chuy” Garcia, who lost to Emanuel in a runoff election in 2015, also reportedly has been mulling another run for mayor, but has yet to announce any plans.

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