A GTA mother wants another police force to open a new investigation into a 2013 car accident that killed one of her sons and left another injured, claiming Durham Regional police did a poor job of investigating.

Joey and Chad Stevenson were crossing Dundas Street East, near Hickory Street, on a snowy night on Feb. 7 when they were hit by a small car. Donna Stevenson, the boys' mother, said 19-year-old Joey died upon impact. Chad, 20, survived but suffered life-threatening injuries that required extensive surgery.

Toronto Durham Regional Police Investigation

Durham Regional Police cleared the driver of this car, which was involved in the fatal 2013 collision. (CBC)

A police report said the driver of the Suzuki Swift, which was equipped with winter tires, remained at the scene and the driver told them he didn't see the brothers at all until he hit them. The man estimated he'd been driving around 60-65 km/h in a 50 km/h zone at the time, but after investigating, police concluded he'd been going 40-45 km/h when he hit the pedestrians and didn't file charges against him.

Donna Stevenson told CBC News she believes the investigation "wasn't done properly."

Stevenson wants the investigation reopened and has also filed a complaint with the Office of the Independent Police Review Director (OIPRD), a civilian oversight agency, against Durham Regional Police for how they handled the case.

OIPRD has assigned her complaint to York Regional Police to investigate.

"There were just too many questions and the answers were just too vague," Stevenson said.

Among Stevenson's questions is how police went about doing the collision reconstruction, the details of which are contained in a 146-page document she has reviewed multiple times.

Stevenson said during the reconstruction police used a different model vehicle with completely different brakes. She also questions how police could clear the driver who told them he had been speeding at the time of the crash.

Expert spots inconsistency in case

Jeff Archbold, a forensic engineer who specializes in reconstruction, said there does appear to be some inconsistency in the case.

Toronto reconstruction expert

Jeff Archbold, a collision reconstruction expert, said police could have done further analysis of the deadly crash. (CBC)

Archbold said police normally use a "skid-to-stop" measurement to calculate how fast a vehicle was going at the time of the collision. He said for the driver to have been going 40-45 km/h as police calculated, he would have had to have seen the pedestrians and started to apply his brakes before the crash — which doesn't square with his statement to police that he didn't see the two men until he hit them.

However, Archbold cautions that when it comes to reconstruction work "you have to remember it's not an exact science," noting "skid-to-stop" measurements only provide a range of speeds.

Archbold said police could have done a "pedestrian thrown" measurement, which measures how far the victims flew after being struck.

Police investigators noted where the two men wound up — one some 75 metres from the collision site and another about 20 metres away — but didn't do any analysis of these numbers, according to the report.

"Normally that's to me a very vital piece of information that helps you do a reconstruction," Archbold said, adding the best estimates combine the results of both measurements. 

Victims were crossing mid-block

The police documents note that both men were wearing dark winter coats and dark-coloured pants when they were struck.

There is no crosswalk where they were crossing, however the area was well lit. The driver told police the roads were slushy and sloppy, but told them he hadn't had any trouble stopping before the collision.

The Suzuki had been recently checked over by a mechanic. The car's windshield was smashed and there was major damage to the vehicle's front-end after the collision.