Const. Jean-Pierre Brabant of Montreal police said the prosecutors' office will wait until the driver's condition improves before laying charges against him.
The young man was driving a Volvo sedan that slammed into a tree and house in Montreal East early Saturday morning.
There were four other people in his vehicle — three men and one woman, all between the ages of 18 and 21.
Two of the male passengers were declared dead in hospital. The other three people in the car, including the driver, were admitted to hospital in critical condition.
All three were upgraded to stable by Sunday morning.
Police said the car was speeding. They are also waiting for blood test results to see whether alcohol played a role in the crash, and are investigating whether the driver was racing with another vehicle.