Former Deputy Director of Gang Investigations James Sanchez stepped down, according to CPD.
This comes after Chicago police opened an internal investigation into some officers' role in a party at a bar. More than 40 maskless people including some police officers were discovered in the bar's back room.
Guide's Sports Club in the city's Southwest Side Garfield Ridge neighborhood was cited last month for COVID-19 violations at that party.
An anonymous allegation claimed the party was for a retiring commander. The Tribune reported the resignation comes after the Jan. 7 party that was for Sanchez.
In a statement, the Chicago Police Department said it "takes this incident seriously" and "Department members who are found to have violated the City's COVID orders will be held accountable."