Nearly one-fourth of the police cars are over a decade old, and an escalating amount are frequently trapped in maintenance facilities, according to a report by the Northern Ireland Audit Office (NIAO).
The Police Service of Northern Ireland (PSNI) operates a fleet of 2,700 vehicles that collectively travel 27 million miles annually.
The organization informed the NIAO about considerable challenges in supplying vehicles for front-line services. It also acknowledged "the possible safety hazards linked to having an aging vehicle fleet."
From 2021 to 2024, the expense for repair work and upkeep carried out in internal workshops amounted to nearly £11 million.
The proportion of the fleet in workshops on any given day has risen from 6% to 16%.
The NIAO said "at its most extreme", almost 500 vehicles were off the road at a given time.
Four years ago, the PSNI launched a strategy setting out plans for the modernisation of its fleet, with the ambition for the average age of vehicles to be five years.
But this has not been achievable, with most vehicles exceeding the target.
Almost £26m has been spent on purchasing new vehicles since 2021.
PSNI fleet management 'critical'
Commenting on the report, Northern Ireland's Comptroller and Auditor General Dorinnia Carville said effective fleet management is "critical" for the PSNI.
She added: "Achieving the planned fleet replenishment rates within the current financial environment will be challenging, however, managing an ageing fleet is also costly, with potentially significant operational impacts.
"This report finds that progress has been made in a number of areas but that there is much more to be achieved, particularly in relation to the introduction of electric vehicles."
The PSNI had planned to have around 700 electric vehicles by next year.
As of last October it had 179.
Electric vehicles are said to be unsuitable for many roles within the PSNI, including an inability to carry the weight of armouring.
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