All four adults riding a quadbike that crashed in Hawke's Bay, leaving a 6-year-old girl seriously injured, could be charged if they won't reveal who was driving, police say.

Ashlee Shorrock remains in a stable condition at Starship children's hospital in Auckland after the crash at Waimarama Beach shortly before midnight on January 2 but none of the adults involved has told police who was at the wheel.

"If we were unable to establish who was actually driving they'll all be charged,'' Senior Sergeant Fred van Duuren of Hawke's Bay police said today.

"There is case law that if you're unable to show who was driving then you can obtain blood from everybody who's suspected of being a driver,'' he said.


Police have taken blood samples from each of the four adults involved to test for traces of drugs and alcohol.

They previously said the types of injuries suffered by people in crashes could often help determine where they were positioned in a vehicle, and who was driving.

The crash was one of a spate of quadbike incidents over the Christmas holiday period ending in death and injury that led to renewed calls for better safety around bike use.