Charges have been withdrawn against Jeffrey Day after a crash that killed his sister and left him severely injured.

The evening of June 19, 2014, Day was driving eastbound on Napperton Drive just east of Kerwood Road when the car left the road, rolled and struck a hydro pole.

Day, then 29 years old, had to be extricated from the vehicle and suffered life-threatening injuries that left him paralyzed. His 27-year-old sister Michelle died at the scene.

Day was facing several impaired driving-related charges in the crash, including criminal negligence causing death, which were laid nearly a year after the incident.

But his attorney Ron Ellis confirms the charges have been dropped.

Ellis added that evidence confirms, "tire treads from the rear passenger tire were about 200 metres (back) from the point of impact between the car and the telephone pole," and the Crown has agreed a blown tire could have been the reason the vehicle left the road.

In addition, the Centre of Forensic Sciences found that Day's blood alcohol level was possibly at zero, and definitely below the legal limit.

Ellis says Day and his mother "were relieved and grateful for the news. This has been hanging over their heads for a long time and they are now finally able to begin the next phase of healing."