Some Phoenix police officers could face criminal investigation in connection with the arrest of protesters last year and falsely accusing them of being in a gang.

The city manager sent a letter Thursday asking the Arizona Attorney General’s Office to get involved.

Phoenix police arrested a group of protestors last year and worked to get them indicted as gang members. The cases were later thrown out.

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But an outside investigation by the law firm Ballard Spahr found that Phoenix police worked backchannels with prosecutors to bring bogus charges.

City Manager Ed Zuercher wrote in a memo to the police chief that certain officers have hurt the reputations of their colleagues and the department. 

“That is not the work that we’re supposed to be doing as the Phoenix Police Department. It’s not what our police officers are supposed to be about,” Zuercher told KJZZ.

Chief Jeri Williams did not know about the effort to charge protesters as a gang, but members of her executive team did. Williams received a one day suspension, and she has demoted three assistant chiefs.

News of the action by Williams came with Zuercher’s release of another probe into a challenge coin used by Phoenix police.

Investigators did not find the origin of the coin, which mocks a protester being shot in the crotch with a pepper ball.

The incident happened in 2017 after former President Trump held a rally downtown.

The coin echoed political speech by Trump and had wording connected to a neo-Nazi phrase. But Ballard Spahr found that Phoenix police did not tie the language on the coin to hate speech. 

“Whether it was hate speech or not, it was extraordinarily disrespectful to someone exercising their First Amendment Rights. And so in that regard, completely inappropriate,” Zuercher said.

The investigation uncovered that police supervisors gave the challenge coin as a gift to subordinates.

Zuercher sent Williams a written admonishment for failures in leadership.