In 17-006372 v Allstate Canada-006372/AABS, 2019 CanLII 43902 (ON LAT), the LAT again addressed the issue of causation in a statutory accident benefits context.  The case involved a  woman who received treatment for psychological issues after an MVA. Her insurer had provided benefits under the non-catastrophic impairment level of funding but denied her claim to further funding. 

Notably, the applicant had a documented history of psychological disorder. The insurer raised the issue of causation on the basis of pre-existing conditions. The parties also disputed the correct legal test for causation.


The  LAT heard evidence that the applicant had previously received psychological treatment. Prior to the accident, she had seen her family doctor multiple times for “anxiety” and “emotional issues”. A psychiatrist also diagnosed the applicant with i) generalized anxiety disorder with panic attacks, and ii) adjustment disorder with mixed emotions. Further, the psychiatrist’s  notes indicated that the applicant suffered from chronic neck pain and she was unable to work due to chronic pain symptoms. He wrote her a prescription for an anti-depressant and a note supporting her application for Ontario Works.

The applicant gave evidence that none of these issues affected her functioning at the time of the accident. This  was corroborated by lay witnesses and her family doctor.


The applicant took the position that “but for” the accident, she would not have sustained the injuries and impairments forming  her claim. In the alternative, she asserted that the accident “materially contributed” to her condition. The insurer disagreed with this conclusion, and submitted that the correct test for causation was the “but for” analysis.

The  LAT agreed with the insurer on the legal test, but concluded that the accident caused the injuries underpinning the accident benefits claim on a “but for” analysis. Despite her pre-existing conditions, the applicant was found to have suffered a catastrophic impairment.


This is yet another decision where the LAT has embraced the “but for” causation test. This continued trend in the case law away from the “material contribution” analysis invites insurers to adjust their claims on the basis of this higher test. This conclusion comes with the cautionary note that LAT decisions are not binding on adjudicators.

The  case is also a warning that a documented history of diagnosis may not end the causation analysis. Evidence from lay witnesses and family physicians remains crucial for establishing medical conditions before and after an accident.

If you have a question about this blog or a similar file, please contact Eric Grossman at 416-777-5222