Medical Malpractice – Essential Elements in Establishing a Plaintiff's Claim in Ontario  

The litigation of a medical malpractice case is one of the most difficult types of claim facing a professional litigation lawyer.

Although the basic principles are relatively straightforward, it is the subject matter which causes the most degree of difficulty and the atmosphere of developing the factual basis for claim that generates the greatest challenge.

In order to establish a claim, it is necessary to demonstrate that there has been a breach in the standard of care and that except for this breach, the damage would not have occurred.

Standard of Care

A breach of the standard of care requires that the plaintiff establish that the defendant physician has failed to provide the care to his patient which an average physician of the same academic qualification licensed to practice in the same area would have provided to that patient.  In other words, it is not the standard which the most skillful physician would have provided nor is it the standard which the least skillful physician would have provided.  Nevertheless, in order to be successful, in our experience we have found that it is necessary to establish basically to the court that no physician practicing in that area would have conducted his practice in the same manner.

It is important to note that a mere error in judgment is not sufficient to establish a breach in the standard of care.  In other words, a physician is given liberty to exercise his judgment in determining a question of diagnosis and/or treatment relating to the patient.  Again, the level of proof basically equates to a statement that no physician would have judged the circumstances in the same manner which this physician did.  The breach in the standard of care can arise in many different ways, the most common of which includes any of the following:

-          sub-standard skill exercised in the performance of a surgical procedure;

-          sub-standard care in the diagnosis of the patient’s condition;

-          sub-standard care in the recommendation for treatment;

-          sub-standard care in the failure to provide adequate warning of the potential risks of any treatment and/or surgical procedure


A.  Sub-standard care in the performance of a surgical procedure

Generally, every surgeon is expected to bring to the performance of his surgery that degree of skill which the average practitioner of that surgical procedure would bring to the operation.  In our experience, these are difficult to establish since no one was available to actually observe the procedure being conducted and a reconstruction to show the inadvertence of a cut too deep or in the wrong place in relation to the joining of organs or tissue are extremely difficult to reconstruct.

B.      Sub-standard care in the diagnosis of the patient’s condition

In every circumstance, a physician is required to make a differential diagnosis of potential causes of the plaintiff’s illness and to propose a plan of action to deal with it.  It’s obvious that some potential may be more likely than others and it is expected that the physician will exercise reasonable judgment in identifying those potential differential diagnoses and ranking their likelihood.

 C.      Sub-standard care in the recommendation for treatment

The most recognizable illnesses have a relatively standardized protocol for treatment which may include surgery, medication, or other forms of care.  The choice of treatment, generally, would be seen as an exercise in judgment and is difficult to attack except to the extent that the particular circumstances relating to this patient might rule out the relatively obvious bases the various forms of treatment which might otherwise be available.

D.      Informed Consent / Sub-standard in failure to warn of potential risks

In warning the patient of the potential risks in connection with alternative treatments available including the effect of having no treatment, a physician must also inform the patient of any risks of death or injury which may be associated to such treatment which might reasonably affect the choice the patient might make.  Even where the risks are minimal, if they involve a potential for death or serious result such as paralysis, then the physician must advise the patient of such. The failure to warn a patient will result in a breach in the standard of care if it can be shown that a patient acting reasonably in the circumstances of that patient, would have chosen not to undertake the treatment proposed.

 Limitation Period

In order to advance a claim, it is necessary for the plaintiff to have commenced the action within two years from the time he knew or ought to have known the facts giving rise to the claim for negligence.

The application of the limitation period is subject to the “discoverability rule” which generally provides that the commencement of the two year period will start at that point and time when a reasonable patient exercising reasonable diligence would have discovered that information which would be reasonably necessary for him to conclude that he had a reasonable likelihood of success in prosecuting a claim in malpractice.

The judicial pronouncements arising under the cases involving this question seem to have a variety of attitudes from the bench varying considerably in the liberality with which judges are prepared to interpret and apply this rule.  Some cases have gone so far as to suggest that until the lawyer acting on behalf of the potential plaintiff has a medical opinion which would demonstrate a breach in the standard of care, the plaintiff would not be in a position to reasonably conclude that he had a reasonable likelihood of success to justify commencing action. 

In other cases, the courts have indicated that until a potential plaintiff has received sufficient information so that he can appreciate that the degree of injury is significant, there would not be any reasonable justification for commencing action and consequently, the limitation period would not commence to run.

An abundance of caution would indicate that an action should be commenced as soon as it becomes ascertainable that there is the possibility of a claim in order to avoid the difficulties attendant with justifying a failure to commence an action within the two year period.

Level of proof

Generally, the degree of proof necessary to establish the facts is the balance of probabilities in the usual manner in a civil action.  This will of necessity require opinions of medical practitioners in the same field who will review and analyze the history of the events leading to the claim for the purpose of identifying specific breaches in the standard of care.  It is not uncommon to have a variety of opinions as to precisely what in fact occurred and whether it is what constitutes a breach in the standard of care.  Consequently, it is important that the experts recruited are recognized as experts of the highest standard of credibility.  Of course, these individuals are in high demand and difficult to recruit.

Issue of cause

Generally, the principle is applicable in a medical malpractice to the issue of cause are the same principles that apply in any negligence action.

The question becomes “but for the negligent action(s) of the defendant, would the plaintiff have suffered the injuries complained of?” 

It is required for the plaintiff to demonstrate on a balance of probabilities that the misbehaviour of the defendant has caused either itself or has contributed in combination with other causes to the injuries of which the plaintiff complains.

Although the degree of proof is only that of a balance of probabilities, nevertheless, medical practitioners, being scientists, find it difficult to address the matter of causation except in more absolute terms.  It is therefore important to ensure that one is not mislead by comments of such practitioners casting doubt on the issue of causation.  The Supreme Court of Canada has ruled that causation should be viewed from a simple common sense point of view to determine which is more probable as the reasonable inference to be drawn by the facts proven, particularly when those facts are peculiarly within the knowledge of the defendant.

 The conduct of the medical malpractice case

Basically, the conduct of a medical malpractice case should be recognized as requiring for attention of a well-experienced litigator.

In Canada , all such cases are defended by the Canadian Medical Protection Association which although it denies that it is an insurer, in effect, provides substantially all of the same services for its members.

The strategy of the CMPA is well recognized in the legal community as being one where they will vigorously defend any claims where there is reasonable possibility that liability can be avoided.

In the adversarial arena, the unlimited resources available to the CMPA to obtain the best level of expert evidence for their defence is a daunting challenge for anyone except the person of well above average financial means.  Counsel employed are extremely well experienced in this form of litigation and can afford the luxury of any pre-trial procedures which they feel may tend to discourage a potential claimant.

The conduct of a claim on behalf of a plaintiff is by and large universally an investigative procedure whereby the plaintiff attempts to determine what really happened by obtaining all of the medical records; conducting a review of them by experts trained to do so; and then prosecuting the claim through the discovery process.  Until all of these steps have been covered, it is almost impossible for counsel to provide any meaningful opinion as to whether the claim is justified while, in the meantime, substantial expense must be incurred to reach this stage.

Potential damages

As in all tort cases in Ontario, the potential for damage awards is limited by the trilogy of cases where the Supreme Court of Canada laid down the limits for general damages which can reasonably be expected as a result of personal injury.  More important, in some medical cases, like in other litigation, the associated claims for loss of income for both past and future, as well as the cost of past and future medical care.  The mult-million dollar cases that one reads about are typically comprised of the amounts awarded for these two factors.  It should always be borne in mind that courts in Ontario are not generous in awarding general damages in comparison to awards in other jurisdictions, particularly south of the border.

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