Major Court of Appeal Ruling in Legate Injury Lawyers Medical Negligence Claim
Following seven years of litigation, we are pleased to report a tremendous win for our clients. The Court of Appeal released Ibrahimova v Cavanagh 2026 ONCA 5731, dismissing the defendant doctor’s appeal on the issue of causation. The decision is important for medical negligence litigation because it clearly reaffirms the Ontario Court of Appeal’s use of principles established by the Supreme Court of Canada in Snell v Farrell, made 30 years ago. In a failure to diagnose case, such as this one, the plaintiff’s burden is to establish a commonsense connection between the negligence and the harm. Our young client was catastrophically injured following a failure to diagnose previable premature preterm rupture of membranes in her 17th week of pregnancy. The failure to recognize and appropriately respond to this time-sensitive medical emergency ultimately led to fulminant sepsis, septic shock, and a near loss of life.
We are proud to recognize Barbara Legate, Alex Wolfe and Luke Kilroy, together with clerks Kim Destun, Molly Barron and Kerry Parsons, for their remarkable efforts throughout this seven-year litigation period. We also acknowledge the exceptional work of counsel, Matthew Sammon, Madison Robin, and Evan Linn.
Background
In Ibrahimova v Cavanagh, the plaintiff, at 17 weeks of pregnancy, attended an emergency department experiencing what should have been recognized as a previable, preterm premature rupture of membranes (May 4 @08:00). This exposed her to infection. A consultation with an obstetrician should have occurred while she was in the hospital. That did not occur, and 2 further visits (May 5 @05:00 and May 6 @17:25 ) and 2 ½ days later (May 02:00) she was in fulminant septic shock, airlifted to a tertiary level hospital and suffered catastrophic injuries.
Causation at Trial
The court accepted evidence that the advice she would have been given by an obstetrician, had the emergency doctor consulted one, included termination of the pregnancy by dilatation and evacuation (D&E) to avoid the dire risks associated with infection of her and her fetus. The trial judge correctly inferred that she would have accepted this advice, taking into account her decisions to have antenatal testing and her personal circumstances. He found that she would have been in a tertiary-level hospital by the afternoon of the consultation.
The plaintiff’s evidence was that she should have been treated by 02:00 May 6 to avoid the injuries. The defendants called evidence from infectious disease to say that the infection abruptly started after the third emergency doctor saw her, progressed rapidly, and the injuries sustained were inevitable. While this theory would have avoided liability for all three emergency doctors, it did not address the counterfactual put forward by the plaintiffs: if the standard had been met, the injury would have been avoided.
Establishing the Counterfactual
The defendants submitted that the plaintiffs should have called evidence from the tertiary hospital and its specialists about how long the process would have taken had she been referred and the priority she would have received.
The court accepted that the trial judge correctly inferred that the medical team would have treated her as a medical emergency and acted without the need to consult infectious disease or wait for signs of sepsis. The court also accepted that the principle in Ediger v Johnson, 2013 SCC 18, that the standard of care must be responsive to the risk of harm, would have applied to those treating the plaintiff at the tertiary center. She would have been treated in a timely manner and dealt with as the emergency she was by those physicians. The court gave a clear statement about the use of indirect evidence and making inferences of fact:
There was no principled reason why the trial judge should not make a finding about when that treatment would have occurred, absent Dr. Cavanagh’s negligence, based on indirect evidence. 2
The Importance of Contrary Evidence
The defendant sought an adverse inference against the plaintiffs from the failure of the plaintiffs to ask the obstetrician if a D&E could be performed within the time frame available before she would be harmed. The trial judge declined to do so, noting that the defendant could have called evidence to disprove the plaintiff’s causation case but did not. The plaintiff proved her case. The defendant did not call evidence to disprove it. The appellate court held that this is not reversing the onus of proof. It stands as a caution to defendants that they risk findings against them if they fail to adduce evidence contrary to that of the plaintiff’s counterfactual.
The Plaintiff's Burden of Proof
The Court concluded with this strong statement endorsing Justice Darla Wilson’s recent clear and blunt articulation of the plaintiff’s burden of proof:
As recently affirmed in Brown v. Meaney, 2026 ONCA 445, at para. 37, the respondents’ burden was merely to show that, on a common-sense basis, Ms. Ibrahimova’s injuries would not have occurred but for Dr. Cavanagh’s negligence. In this case, as in Brown, the trial judge determined that this burden had been met. This determination was untainted by any reversible error.3
Key Takeaways
This decision provides the limelight on the importance of a common-sense approach to causation in medical negligence cases. It reaffirms that causation can be established through indirect evidence and reasonable inferences where the evidence supports the conclusion that the injury would not have occurred without the medical negligence. The decision also clarifies that defendants challenging a plaintiff’s counterfactual must present evidence capable of disproving it.
For our client, the Court of Appeal’s dismissal of the appeal after seven years of litigation is a significant victory and a strong reaffirmation of the principles governing causation in medical negligence claims. For our client, the Court of Appeal’s dismissal of the appeal after seven years of litigation is a significant victory and a strong reaffirmation of the principles governing causation in medical negligence claims.
