Portland police continue to spend millions of dollars in overtime with little effort to manage or limit costs, a city audit found.

One officer worked 97 hours in one week last year.

While that’s an extreme case, patrol officers worked more than 20 hours of overtime in one week 1,100 times in 2018, according to the audit made public Tuesday.

The bureau spent $15.7 million in overtime costs in 2018, with officers working nearly 250,000 extra hours, slightly down from 2017 but higher than prior years.

Poor data collection and reporting of overtime limited supervisors’ ability to manage patrol officers’ overtime, the report said.

Though bureau managers blame severe staffing shortages for the majority of overtime costs, they couldn’t back up that claim with data, the audit said.

“Bureau staff at all levels said there was no sense in looking for ways to limit overtime because of the existing personnel shortage. We found that reasoning to be based on faulty assumptions that overtime data were reliable and management decisions about when to use it were sound,’’ the report said.

Faulty software updates in the bureau’s daily officer assignment system had sergeants double-filling some shifts, auditors said. The computer system was “randomly dropping’’ officers who signed up to fill shifts on overtime, so sergeants would have another officer sign up for the vacant patrol spot.

That foul-up continued for six months before it was detected.

“Both officers would show up for duty and work the shift, but only one was really needed. ... Bureau staff was unable to determine how many shifts were affected and how many overtime hours were incorrectly recorded," the audit said.

Neither sergeants, who make day-to-day decisions on whether to offer overtime to patrol officers, nor precinct commanders adequately monitored overtime spending, auditors found.

“Whether a City bureau is staffed appropriately or not, overtime use must be well managed,” City Auditor Mary Hull Caballero said. “Exhausted and overworked officers pay a price in terms of their own well-being, and the community shoulders the cost in the quality of police services they receive.”

The audit recommended the bureau take more aggressive steps to approve, administer and report overtime work. It also said Portland police should limit the amount of overtime an officer can work, such as the Denver and San Francisco police departments do.

“An overtime limit could give sergeants an objective tool to make it easier to tell an officer that they have already worked too much overtime and need to let another officer pick up a shift,’’ the report said.

Portland Police Chief Danielle Outlaw said the bureau is planning to adjust patrol shift schedules and precinct minimum staffing levels based on public safety needs to reduce overtime costs. It also has improved tracking overtime hours with a new system adopted in February, the chief said.

The bureau also will consider negotiating a cap for officer overtime with the union, the chief said.

“While we are always looking for ways to better manage the use of overtime, the bulk of our overtime expenditure is driven by personnel shortages, particularly at our three patrol precincts,'' Outlaw wrote in a response to the audit.

As of early August, the Police Bureau had 133 officer vacancies in an authorized police force of 1,001 officers, according to the bureau.

Overtime hours worked in 2018 were down from 2017 but still higher than prior years, according to the city audit.

Sometimes overtime occurred because sergeants approved too much vacation leave, the review found. Under bureau guidelines, only 10 percent of officers assigned to a shift should be authorized for leave at a time. Approving too much leave at one time led to overtime in 18 percent of patrol shifts, the audit said.

North Precinct approved leave at the greatest rate, causing overtime for 41 percent of its afternoon shifts in 2018.

The audit also found that one officer stayed after a shift ended to finish up writing reports on 40 different occasions, earning overtime each time. Five other officers were paid overtime to complete their reports more than 30 times. One officer worked more than 20 hours of overtime a week for 27 weeks in 2018.

The audit also identified risks in secondary private jobs, which officers receive overtime pay to work. Those risks include unequal treatment in contracts approved (police provided security for a Southern Poverty Law Center private event but rejected a contract for the conservative Oregon Liberty Alliance); some business owners want police for visibility but direct them not to make arrests if they witness a theft or other crime; some business owners have asked police to target people of color.

“The risks associated with secondary employment may outweigh the public benefit if the Bureau is not consistent in applying criteria for selecting which contracts to approve,’’ the audit said. “With inconsistent documentation, risks associated with secondary employment, such as officer fatigue, racial inequity, and political favoritism, could outweigh the benefits.’’

There was little tracking of secondary job overtime, according to the audit, and union contract requirements were violated. According to the audit:

-- Officers are restricted to 20 hours a week of secondary employment, but 14 officers or sergeants violated that limit 39 times in 2018. One person violated the limit 10 times.

-- Officers aren’t supposed to get time off instead of overtime pay for secondary employment, but they did in 71 instances in 2018.

“Time off at a future date instead of payment is problematic, because when patrol officers take time off, they can be backfilled with someone on overtime. The hour and a half of time off an officer received as compensation for working secondary employment could become 2.25 hours of compensation if an officer is needed to backfill the position,’’ the audit noted.

In fiscal 2017-18, the bureau billed secondary employment customers $1.8 million and paid officers and sergeants $1.4 million in overtime wages, with a difference of $400,000. But overtime wages didn’t include all of the administrative police costs of secondary employment, such as approving contracts , processing payroll and billing customers, the analysis said.

Officer Daryl Turner, president of the Portland Police Association, declined Tuesday morning to comment on the report’s findings.

-- Maxine Bernstein

Email at mbernstein@oregonian.com

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