A London judge has found that drug consumption led to a collision that had catastrophic consequences for members of a St. Thomas family.

With that finding, Superior Court Justice Marc Garson found 31-year-old Nathan Hathaway guilty on four counts of dangerous driving causing bodily harm and four counts of impaired driving causing bodily harm.

The ruling was in connection to a July 24, 2016 collision that caused serious, life-altering injuries to members of the Williams family who had just spent an evening at the Mustang Drive-In Theatre on the southeast edge of London.

The crash caused their pickup to flip into the ditch.

Kevin and Victoria Williams and their four children, ranging in ages from five to 13, had just pulled onto Wilton Grove Road, heading west toward Highbury Avenue South when their four-door, crew cab GMC Sierra pickup truck was hit head on by a Nissan Rogue SUV driven by Hathaway.

Both Kevin, 51, and Victoria, 45, received serious brain injuries along with other physical trauma which have left her with persistent hearing and vision issues.

One daughter, 10-year-old Olivia, had bones crushed on one side of her face and suffered a fractured arm that has left it slightly shorter than her other arm. Olivia was in the front seat of the truck between her parents.

The three other children Ariel, Shawna and Hunter - ages 13, 8, and 5 at the time - received less serious injuries.

A woman and child in Hathaway’s vehicle also suffered minor injuries.

Hathaway was taken to hospital to be treated for minor injuries at which time a blood sample was taken. That sample indicated Hathaway had methamphetamine and methamphetamine metabolite in his system.