A Wellington coroner is urging the Transport Minister to review the law involving doctors driving to emergency calls.
It follows the death of a woman in Hutt Hospital in 2008 from respiratory failure.
The inquest was told the consulting physician was urgently called back to the hospital in Lower Hutt but was stopped by a police officer for speeding.
The doctor was breath-tested, before being allowed to continue.
Coroner Ian Smith says while he is satisfied the delay of up to five minutes did not contribute to the woman's death, he is concerned that a similar situation could arise.
Any review should deal with the use of green flashing lights by medical staff or other such warning devices, or even the use of police escorts, he says.
Police say district health boards should consult with them to develop policy and guidelines on warning lights.