Police were justified in sending a dog after a drunk man who refused to exit a crashed vehicle following a lengthy and violent chase that started in Calgary and ended near High River, according to a review of the 2014 incident.

"It is due, in large measure, to the effective deployment of the police service dog that the safety of officers on scene was secured," the Alberta Serious Incident Response Team (ASIRT) said in a summary of its investigation results.

The driver suffered serious bite injuries after police smashed a window in the disabled vehicle at the conclusion of the chase, allowing the dog to jump inside and drag the man out by his arm.

This came after an initial deployment of the dog and several unsuccessful attempts to use pepper spray to subdue the driver, who remained defiantly inside the vehicle, revving the engine and spinning the flat tires, after officers disabled it with a spike belt.

The driver was found to have a blood-alcohol limit of 0.318 per cent, which is almost four times the legal limit and within the range of intoxication that can be fatal to human beings.

Police initially became aware of the vehicle due to an impaired driving complaint and quickly realized it was stolen when they came across it in downtown Calgary.

The driver refused to stop and led officers on a long southward chase that saw him intentionally ram other vehicles before finally being stopped south of Calgary near High River by the spike belt.

"The driver engaged police in a lengthy pursuit during which he drove in an egregious and dangerous fashion, intentionally colliding repeatedly with a woman's vehicle that just happened to be on the road he was taking, and colliding with vehicles belonging to two other civilians," said ASIRT in a release. "He also intentionally rammed an RCMP police vehicle, disabling it."

The driver told ASIRT investigators he had decided he wasn't going to give the vehicle up, even after it was disabled.

"The driver did not follow the direction of police, continued to attempt to operate the vehicle, which was in gear, and he was not deterred by the first deployment of the dog or the use of pepper spray," the report states.