An Ontario court of justice has acquitted a Brampton, Ont., man of impaired charges in relation to the Burlington Skyway crash in 2014 because police mishandled the driver's blood alcohol test.

While the breath test police took showed dump truck driver Sukhvinder Rai registered nearly three times the legal limit of alcohol in his blood, that evidence was ruled inadmissible because it was obtained too long after the crash.

The raised rear box of Rai's dump truck slammed into the bridge superstructure on July 31, 2014. The bridge was closed for four days after the accident, shutting down a key provincial artery over a holiday weekend. It cost more than $1 million to repair damage to the bridge.

On Wednesday morning, Judge Fred Campling in the Hamilton court threw out an impaired driving charge and a charge of driving with a blood alcohol level over 80 mg, leaving the 36-year-old with five remaining charges: dangerous driving and four counts of mischief endangering life.

Rai has pleaded not guilty to the remaining charges.

Earlier in the trial, a breath test analyst testified the test was taken five hours after the collision.

On Monday, Campling said Ontario Provincial Police officers demanded a breath test from Rai too long after he was sitting in the driver's seat. Campling said this demand was a breach of Rai's protections under the Charter of Rights and Freedoms. Breath tests must be made within three hours of the accused being behind the wheel, as outlined in the Criminal Code.

The Crown had argued the unique circumstances and chaos created by the crash were enough to warrant an exception to the time limit.

With the breath test results no longer being accepted as evidence, the court heard there was no reasonable prospect of conviction on the impaired charges, leading Campling to acquit on the two charges.

Truck testing called into question

On Wednesday afternoon, defence attorney David Locke called Centennial College automotive teacher James Hooey to testify about the hydraulic systems in trucks.

Hooey said he watched a video shown to the court Tuesday of how the components of the dump truck were tested.

He criticized how the testing was conducted for the criminal trial. He said the tester used a new pump valve when testing the hydraulic system and an inappropriate gauge for a pressure test.

Hooey also commented on what the court heard on Tuesday regarding how Rai left the power-takeoff system — which is part of the system for raising and lowering the box — engaged for a long time prior to the crash on the Skyway bridge.

Box could rise on its own, expert says

Hooey said that with the PTO engaged, if a certain control valve was leaking and pressure was building up in the system, it's possible the box on the truck could have gone up on its own when the engine's rpm reached a certain level. He said as drivers gear down when climbing a hill (or the ramp of a bridge), the truck engine's rpm would get much higher, making this scenario possible.

"A safe driver would check to make sure the PTO was off [before driving], right?" asked Crown prosecutor Todd Norman.

"A safe driver would, yes," Hooey replied.

The Crown wrapped up its case on Tuesday, and on Wednesday afternoon the defence lawyer Locke told the court he was finished giving evidence.

Locke is expected to bring forward issues around alleged violations of Rai's charter rights in court on Thursday.

The trial is scheduled to end by March 29, but Campling could rule on the remaining charges as early as next week.