The 128-page report says SFPD spent over $108 million on overtime during the 2022-2023 financial year.
Among the other findings, the report states that the department failed to adequately monitor or enforce overtime limits.
It also says that around 200 officers, or about 12% of sworn staffers, accounted for about a third of the total overtime budget.
Additionally, the audit highlighted that the average employee took over 25 days of sick leave a year, up from 14 during the 2018-2019 financial year.
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Outgoing San Francisco Supervisor Dean Preston commissioned the audit.
"Some really shocking findings. One of the biggest of which is the use of sick time to then go work, get overtime work working for private companies," Preston said.
Preston believes the city has let SFPD spend too much money for too long.
He says that's especially true given the multi-million dollar deficits San Francisco faces.
"I've got constituents who are facing service cuts. Folks who rely on the city for food aid, for other forms of relief. Everyone's being told it's a deficit and you need to cut. Meanwhile, this audit shows the police department is on a spending spree," Preston said.
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Incoming Mayor Daniel Lurie says he hasn't yet had a chance to review the audit, but told us he's committed to getting SFPD back to full staffing levels.
ABC7 News reporter Tim Johns caught up with Lurie briefly Thursday afternoon.
"We are too short-staffed. We rely too heavily on mandatory overtime," Lurie said.
That sentiment was echoed by SFPD who says it is currently about 500 officers short. It sent us a statement responding to some of the audit's criticism.
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It reads in part: "As a necessary stopgap measure, the SFPD has been using overtime to backfill our patrol and investigation units to ensure San Francisco remains one of the safest cities in the country. As we continue to rebuild our ranks, overtime hours will decrease, saving the city money and giving our incredibly hard-working officers a much needed break."
It's an explanation Preston says isn't good enough.
"If a nonprofit that we as a city had contracted with was shown to have this lack of oversight in their spending and this level of abuse of city money, we'd either be terminating the contract with that nonprofit or at least putting them on probation," Preston said.
The supervisor says he wants to see the city take a more active role in providing oversight for SFPD.