A police officer who was seriously injured when a lorry hit his unmarked car, had covered its emergency lights with nylon tights, a watchdog has revealed.
The BMW was hit in a layby after he moved to avoid a vehicle which moved into his lane on a dual carriageway.
The officer later told investigators that he had covered his unmarked car's emergency lights with nylon tights before it was involved in a crash, an independent watchdog has revealed.
An investigation by the force, North Wales Police, found the tights had significantly reduced the light output.
The Independent Office for Police Conduct (IOPC) has now said there should be a national policy on covering lights.
It concluded the improvised covering could not be ruled out as a contributory factor to the crash – because it made it “extremely difficult” for the driver of the vehicle on the dual carriageway to see the flashing lights.
The subsequent IOPC investigation identified no national standards for such covering. It found a number of police forces across the country were using various methods – including nylon tights.
Catrin Evans, the IOPC's director for Wales, said: "Any modifications made ought to be tested and approved by experts rather than ad hoc solutions that may not be the safest method. For the safety of police drivers and the public alike, testing would also help make sure that any coverings do not significantly limit the visibility of the emergency blue lights."
The IOPC's recommendations have been accepted by the National Police Chiefs' Council which has now commissioned a working group to produce the new policy.
The watchdog found no case to answer for the officers involved in covering the grille lights.
No members of the public were hurt in the crash.
