The Honolulu Police Department has seen an increase in staffing vacancies in recent years, a condition that hasn’t resulted in cost savings, according to a city audit. Instead, the report shows uncontrolled overtime spending, with a relatively small group of employees really cleaning up on the taxpayer’s dime.

Part of this is plainly due to inefficient, outdated methods of accounting for overtime hours, a system that must be overhauled. The auditor also rightly cites a lack of oversight in a system that rewards a select few rather than serving the public.

Those are conclusions of the audit, released Friday, with an array of stunning figures. Over the past five years, almost $30,000 in overtime payments were claimed but were unsubstantiated. The city’s pension liability, due to inflated salaries of those who then retire, increased by as much as $6 million.

The 10 top OT earners, unidentified in the report, claimed 76,726 overtime hours and collected more than $4 million over that period. By itself, that is a vulnerability to abuse that HPD must close.

City Auditor Arushi Kumar found the manual method of accounting for the OT hours as a factor “increasing the risk for error, abuse and fraud.” Managers acknowledge the volume of handwritten timecards produced for its more than 2,100 officers, and that meant some cards would go missing, leaving gaps in documentation.

Additionally, and more importantly, while HPD has policies and procedures in place, “inconsistent interpretation and application of those controls resulted in ineffective management of police overtime.”

This conclusion was based on a survey distributed to the department’s 22 supervisors, and on interviews with supervisors, who had varied responses when asked about the existence of overtime limits.

Obviously, this is a problem, and while it is positive that HPD officials have owned it in response to the audit, fixing the process will be a big job.

It’s one that newly appointed Police Chief Arthur “Joe” Logan, who was not involved in the audit, must now embrace, along with efforts to improve recruitment and retention of officers in an understaffed department.

That problem is well documented in the audit, which traces vacancies rising from 178 in 2016, to 303 in 2020. Overtime generally has increased along with vacancies, although the pandemic suppressed both the crime reports and overtime claims.

Another crucial step would be full cooperation from the State of Hawaii Organization of Police Officers. The union has said the audit validates its assertion that staffing deficiencies must be corrected. It does, but that’s not the only thing it exposes: There needs to be accountability to see that spending is justified and equitable.

The labor representatives of the police officers need to step up and be part of the solution, even if it means the oversized pay packets of some members would shrink. The department is considering reducing staffing for some shifts and beats to reduce costs, as well as sharing resources across districts and beats to cover the most intensive public-safety needs.

This only makes sense as HPD strives to balance its resources and work requirements.

The police department has struggled to overcome a recent history plagued with scandal, mostly due to the corruption convictions of several top officers, including former Chief Louis Kealoha. Homelessness, gun violence and other social ills have added to the complexity of the mission.

In response, Honolulu can’t afford to enable more waste and abuse. HPD, with the Police Commission’s oversight, must move swiftly toward a system that gets the job of public safety done efficiently — and fairly.