Ryan was taken to hospital but was discharged.
Senior Constable Karl Bevin, of the Waitemata serious crash unit, said alcohol and speed were factors in the crash.
Mr Bevin, who attended the scene, said the passenger who was thrown from the vehicle suffered the worst injuries.
Hospital spokesman Mark Fenwick confirmed last night that Allen was still in hospital and that he was in a stable condition. He could not say what the nature of the surgery was, but Allen was being prepared to go into theatre.
Police are speaking to the driver of the vehicle, who tried to escape from officers by jumping into the Waitemata Harbour.
Mr Bevin said officers managed to get to the man with the help of a dog team.
Police spokesman Ben Offner said the man "had a slight wade or swim, but he came ashore quite quickly".
Police did not know why the driver tried to evade police.
"I'm sure there is a good reason for it," said Mr Offner. "but at this stage I don't know what it is."