Denver’s top public safety leader says he is prepared to discipline and even fire police officers, sheriff’s deputies and firefighters who don’t abide by the city’s requirement that all city employees get vaccinated against COVID-19.

“That order says city employees shall be vaccinated. If our folks don’t comply with it in the time that is allotted by the mayor’s office and the Department of Public Health and Environment, then I am prepared to do what is necessary to hold people in compliance and hold people accountable,” said Murphy Robinson, executive director of the Department of Public Safety. “That’s my job.”

The public health order issued Monday by the city health department requires all city employees to receive their second shot by Sept. 15 and provide proof of vaccination, the Denver Post reports.

The Denver police officers’ union on Thursday said in a statement that it “respects and trusts our members with their own choices on how to maintain their health, the health of their families, and the health, safety and welfare of the citizens of Denver in a profession that exposes them on a daily basis to violent criminals, as well as multiple contagious and infectious diseases prevalent in our community.”