As a lawyer helping people with medical malpractice cases, one of the most difficult tasks for me is to explain to an injured client and/or their family members the reality that in some cases, while the medical professional may be found negligent, the negligence did not cause the injury. The result: even though the medical professional was negligent, the injured client receives no compensation.

This is the tricky issue of causation, which is a primary and at times the only issue in medical malpractice cases. This concept is even more difficult when there are a number of medical professionals who could potentially be at fault — in those cases, a jury can be confused as to how to assess the issue of causation.

A recent case from the Ontario Court of Appeal, Sacks v. Ross, helps clarify how juries should decide causation issues where multiple defendants exist. While the plaintiff in that decision ultimately lost the case and the appeal, the decision is helpful to those who have been injured by medical malpractice.

The Facts of Sacks v. Ross

The plaintiff, Jordan Sacks, went to Sunnybrook Hospital for routine bowel surgery.  An anastomotic leak occurred after the surgery, spilling the contents into Mr. Sacks’ abdominal cavity.

The defendants acknowledged that an anastomotic leak must be treated quickly to prevent infection, sepsis and septic shock, but the discovery of the leak in Mr. Sacks was delayed. By the time the leak was detected, Mr. Sacks was in septic shock. The infection was so severe, that both of his legs had to be amputated below the knees as well as all of his fingertips.

Mr. Sacks argued at trial that the delay in diagnosing and treating the leak caused him to go into septic shock and the resulting amputations. He argued that the delay was the result of multiple errors made by his treating doctors, nurses and other medical professionals at Sunnybrook Hospital.

Meanwhile, the defendants argued that the delay in diagnosis and treatment did not cause Mr. Sacks’ injuries. The reason: Mr. Sacks contracted a rare, unrecognized aggressive flesh eating disease in his right lower back, which could not have been diagnosed or treated when it first arose.

The jury found five of the defendants negligent in their treatment of Mr. Sacks. However, the jury did not find that the defendants’ negligence caused Mr. Sacks’ injuries. The case was dismissed and Mr. Sacks received no compensation.

The Appeal

Mr. Sacks appealed to the Ontario Court of Appeal. He argued that the trial judge did not properly instruct the jury on how to consider the issue of causation. The Court of Appeal considered the following three questions:

1. Did the trial proceed on a correct understanding of causation in negligence cases?
2. Were the jury questions and the jury instructions on causation legally correct?
3. Did any legal error in the jury questions or the jury instructions deprive Mr. Sacks of a fair trial?

In considering the first issue, the Court of Appeal set out the following three-step process in determining causation:

1. Determine what likely happened in actuality on the facts of the case that the jury accepts.
2. Consider what would likely have happened had the defendant(s) not been negligent.
3. Allocate fault among the defendants found to be negligent.

When considering the second step, the Court of Appeal directs that the jury must look at the evidence and determine if the plaintiff would likely have been injured in any event, regardless of what the defendant(s) did or failed to do.

If the jury decides that the plaintiff would have been injured even if the defendant(s) was not negligent, causation is not made out and the defendant(s) is not liable. On the other hand, if the jury determines based on the evidence that the plaintiff would not likely have been injured without the defendant(s)’s negligence, the test for causation is satisfied and the defendant(s) will be liable for the plaintiff’s injuries.

As noted by the Court of Appeal, this causation analysis becomes complicated when there are multiple defendants.  For example, while no one particular defendant’s negligence alone may be sufficient to have caused the plaintiff’s injuries, the collective negligence of multiple defendants may have caused the plaintiff’s injuries.

In cases where there are multiple defendants, the Court of Appeal directs that a jury must first consider whether the collective negligence caused the plaintiff’s injuries. If yes, the second question considers the negligence of the individual defendants.

On this basis, the jury should have been asked the following three questions on causation:

• Have the plaintiffs proven on a balance of probabilities that a delay in treatment caused Jordan Sacks’ injuries?

If the answer to that question is “yes”, in respect of each individual defendant:     

• Have the plaintiffs proven, on a balance of probabilities, that the delay in resulting from [this defendant’s] negligence caused or contributed to the injuries of Jordan Sacks?

If the answer to that question is “yes”, in respect of each individual defendant:

• How did [this defendant] breach the standard of care (i.e. negligent)?

Unfortunately for Mr. Sacks, while the Court of Appeal agreed that the trial judge did not properly instruct the jury on causation or in the formulation of the jury questions, it did not find that the jury’s verdict would have been different if properly instructed. The Court of Appeal dismissed his appeal.

While Mr. Sacks was left with no compensation and no remedy for his injuries, this decision provides clarity on the application of causation in medical malpractice cases involving multiple defendants. This decision should resolve the unfair conundrum that multiple defendants may be negligent but each could avoid liability by suggesting that the negligence of each other caused the injury.

Overall, while not a good or fair result for Mr. Sacks, this decision will be helpful to future victims of medical malpractice where there is more than one negligent defendant.