L.A. County Sheriff Alex Villanueva is targeting his critics using a little-known investigative unit of deputies to open criminal inquiries into his political enemies, according to the Civilian Oversight Commission. Members of the commission have spoken of their concerns about the unit’s apparent lack of results. “These highly publicized criminal investigations have never resulted in charges filed, suggesting an ulterior motive,” one member wrote. Villanueva has dismissed the allegations, saying that his team is a tool for fighting corruption. Multiple sources told the Los Angeles Times, however, that the unit is sometimes referred to internally as the sheriff’s “secret police.”

The sheriff has also been accused of allowing “gang-like” groups of deputies, some with matching tattoos, to operate under his purview. Some of these gangs face claims of violent misconduct: hazing, beating up inmates, and withholding backup for other deputies in active danger. The COC ordered Villanueva to appear before them on Thursday to answer questions about his alleged abuses of power. Villanueva has cited a busy schedule as the reason he won’t be appearing.