The Chicago Police Department is under fire over its decision to not dismiss an officer who lied about ties to the far-right Proud Boys group.

Police Superintendent David Brown says investigators “were not able to prove by a preponderance of the evidence that this officer was a member of, or was associated with, the Proud Boys, or any other hate group.”

The officer was instead suspended for 120 days.

However, the Office of the Inspector General urged Brown to consider firing the officer because they violated departmental rules prohibiting the making of false reports.

“I don’t think extremism in the ranks of law enforcement is an overwhelming issue, but even a few officers being involved in these kinds of groups can cause real problems,” said Jared Holt, senior research manager at the Institute for Strategic Dialogue.

Earlier this fall, the Anti-Defamation League released a report identifying over 370 people it believes currently work in law enforcement nationwide that were included on a leaked far-right Oath Keepers membership list.

The report notes that appearing in the Oath Keepers’ database doesn’t prove that person was ever an active member of the group.