CHICAGO • The head of the Chicago police officers union has called on its members to defy the city’s requirement to report their COVID-19 vaccination status by Friday or be placed on unpaid leave.

In the video posted online Tuesday and first reported by the Chicago Sun-Times, Fraternal Order of Police President John Catanzara vowed to take Mayor Lori Lightfoot’s administration to court if it tries to enforce the mandate, which requires city workers to report their vaccine status by the end of the work week. After Friday, unvaccinated workers who won’t submit to semiweekly coronavirus testing will be placed on unpaid leave.

Catanzara suggested that if the city does enforce its requirement and many union members refuse to comply with it, “It’s safe to say that the city of Chicago will have a police force at 50% or less for this weekend coming up.”

In the video, Catanzara instructs officers to file for exemptions to receiving the vaccine but to not enter that information into the city’s vaccine portal.

He said that although he has made clear his vaccine status, “I do not believe the city has the authority to mandate that to anybody, let alone that information about your medical history.”

During a news conference Wednesday, Lightfoot accused Cantazara of spreading false information and dismissed most of his statements as “untrue or patently false.” She said COVID-19 vaccines are proven to be effective and that getting vaccinated would protect city workers and their families.

“What we’re focused on is making sure that we maximize the opportunity to create a very safe workplace,” Lightfoot said. “The data is very clear. It is unfortunate that the FOP leadership has chosen to put out a counter narrative. ”

She said the city is prepared to deal with any fallout to the vaccination requirement. Violent crime has spiked in the city this year, from expressway shootings to a rise in carjackings. Chicago police reported 629 homicides this year through early October, compared with 605 during the same period last year.