Do I Have a Medical Malpractice Case in Ontario? The 4 Things You Must Prove

Something went wrong with your medical care, and you are living with the result. Maybe a diagnosis was missed, a surgery left you worse off, a medication caused harm, or a loved one died when you were told they would recover. It is natural to feel that a doctor or hospital should answer for it. But a bad medical outcome, even a devastating one, is not the same thing as a medical malpractice case. To win a medical malpractice claim in Ontario you have to prove four separate things, and each one is its own battle.

Here is the short answer up front. You do not have a case just because you were harmed. You have a case only if you can prove all four of the following: that the provider owed you a duty of care, that the care fell below the accepted standard, that the substandard care actually caused your injury, and that you suffered real, measurable harm as a result. Miss any one of the four and the claim fails, no matter how sympathetic your situation is. The hardest of the four, in most cases, are the middle two: proving the care was substandard, and proving that the substandard care, and not your underlying illness, is what hurt you.

This guide walks through each of the four elements in plain language, using the leading Supreme Court of Canada decisions that Ontario courts still apply today. It explains the standard of care and why doctors are not judged with hindsight, the "but for" test for causation and why it is so hard to meet when a patient was already sick, the kinds of harm you can claim, and the deadlines that can quietly end a claim before it starts, including the separate, unforgiving deadline that applies when a patient has died. The core rules come from the common law of negligence, the Limitations Act, 2002, and, for a deceased patient, the Trustee Act.

If you think you or a family member may have been harmed by negligent care, do not try to judge these four elements on your own, and do not wait. Speak with a personal injury lawyer early, because medical malpractice claims turn on medical records and expert evidence that take time to gather, and the deadlines are strict. This article is general information about Ontario law. It is not legal advice, and reading it does not create a lawyer and client relationship. Every claim turns on its own facts and medical evidence.

What is medical malpractice in Ontario?

Medical malpractice is not its own special area of law. In Ontario it is simply the law of negligence applied to health care. There is no statute called the "Medical Malpractice Act." When people say medical malpractice, they mean a claim that a doctor, nurse, hospital, or other health care provider was negligent, and that their negligence injured a patient.

Because it is a negligence claim, it rests on the same foundation as any other negligence case, from a car crash to a slip and fall. The injured person, called the plaintiff, has to prove four elements: a duty of care, a breach of the standard of care, causation, and damages. What makes medical malpractice distinct is not the legal test. It is how technical and expert driven the proof is, how well funded the defence usually is, and how often the patient was already ill, which makes it genuinely difficult to separate the harm caused by negligence from the harm the illness would have caused anyway.

It is worth naming what medical malpractice is not, because these are the most common misunderstandings. It is not a guarantee of a good result; even excellent care can end badly. It is not the same as being unhappy with your doctor. And it is not proven simply by pointing to a poor outcome and working backward. The law asks a narrower question: did the care fall below what a reasonable provider would have done, and did that failure cause your injury?

Providers who can be sued include family doctors, specialists, surgeons, anaesthetists, emergency physicians, nurses, midwives, dentists, pharmacists, and the hospitals and clinics that employ or credential them. A hospital can be liable both for the negligence of its own staff and, in some situations, for its own institutional failures, such as inadequate systems or understaffing.

What are the 4 things you must prove in a medical malpractice case?

To succeed, you have to prove each of the four elements below on a balance of probabilities. That phrase simply means "more likely than not," or more than 50 percent. It is a lower standard than the "beyond a reasonable doubt" test from criminal law, but in a medical case it is still demanding, because the facts are complicated and the evidence is fought over.

Think of the four elements as four gates. You have to pass through all of them, in order. A claim can be strong on three gates and still fail completely at the fourth. The table below sets them out, and the rest of this guide takes each one in turn.

Notice what the table shows. The first and fourth gates are usually the easiest: it is rarely disputed that your doctor owed you a duty of care, and if you were genuinely injured, damages exist. The whole fight, in most cases, happens at gates two and three, and those questions are decided almost entirely on expert medical evidence, where cases are won and lost.

Element 1: Did the provider owe you a duty of care?

A duty of care is a legal obligation to take reasonable care to avoid harming someone. In medical malpractice, this element is usually the simplest of the four, because the doctor and patient relationship almost always creates a duty automatically.

When a physician agrees to assess or treat you, the law imposes a duty to exercise reasonable care and skill. The same is true of a nurse caring for a patient on a ward, a surgeon in an operating room, a pharmacist filling a prescription, or an emergency physician who takes you on as a patient. Once the professional relationship exists, so does the duty. You do not have to prove a contract, and you do not have to prove the provider promised anything. The duty flows from the relationship itself.

Because it is so rarely in dispute, the duty element is often conceded by the defence. There are edge cases where duty is genuinely contested, such as a hallway "curbside" opinion about a patient the doctor never formally took on. But in the ordinary case, if a provider was treating you, they owed you a duty of care, and the real fight moves on to the next gate.

Element 2: Did the care fall below the standard of care?

This is the heart of most medical malpractice cases. Proving a duty existed is easy. Proving the provider breached it, by falling below the accepted standard of care, is where the majority of claims succeed or fail.

What is the standard of care?

The standard of care is the level of skill and care the law expects of a reasonable provider in the same position. The leading case is the Supreme Court of Canada decision in ter Neuzen v. Korn, 1995 CanLII 72 (SCC), which Ontario courts still rely on today. The core principle is that a doctor must conduct their practice in accordance with the conduct of a prudent and diligent doctor in the same circumstances.

Two refinements matter. First, a specialist is held to the standard of a reasonable specialist in that field, not that of a general practitioner. Second, the standard is not perfection. The law does not require the best possible care; it requires reasonable, competent care. A provider can make a judgment call that turns out badly and still meet the standard, as long as it was one a reasonable provider could have made at the time with the information available.

Are doctors judged with hindsight?

No, and this is one of the most important and least understood parts of the standard of care. In ter Neuzen v. Korn, the Supreme Court was clear that a doctor is judged by the standard of knowledge at the time of the alleged negligence, not by what medicine learned afterward. What matters is what a reasonable provider knew or should have known then.

The facts of ter Neuzen show why this matters. The plaintiff contracted HIV through artificial insemination performed by the defendant physician in the mid 1980s. By the time of trial, the risk of HIV transmission through that procedure was well understood. But the question the law asks is whether a reasonable practitioner would have appreciated that risk at the time the treatment was given, when the medical community's understanding of HIV was still developing. Judging the doctor by later knowledge would be unfair, because no amount of care can guard against a risk the profession did not yet recognize. This "no hindsight" rule is a frequent battleground, because the parties often disagree about what was actually known at the relevant time.

Does following common practice protect a doctor?

Usually, but not always, and the exception is important. Where a case involves technical matters beyond the ordinary knowledge of a judge or jury, the standard of care is generally established by expert evidence about what accepted or approved practice was. If a provider followed a recognized, standard practice, that will normally show they met the standard of care.

But ter Neuzen also recognized a crucial exception. A standard practice is not automatically reasonable. Where a common practice is itself fraught with obvious risks, such that anyone could see it was negligent without needing medical expertise to judge it, a court can find even a widespread practice negligent. In other words, "everyone does it this way" is a strong defence, but not an absolute one. This exception is narrow, but it means an entrenched habit is not a shield when the risk was plain.

Is a bad outcome proof that the standard was breached?

No, and this is the single most common misunderstanding about medical malpractice. A poor result, even a catastrophic one, does not by itself prove the care was negligent. Medicine deals with sick people, unpredictable bodies, and treatments that carry known risks, and some patients get worse or die despite flawless care. To prove a breach, you must show what a reasonable provider would have done differently, and that the provider failed to do it, judged by the knowledge available at the time.

This is why the standard of care is proven with expert evidence rather than argument. A qualified expert, usually a provider from the same field, reviews the records and gives an opinion on what accepted practice required and whether the care fell short. Without a supportive expert opinion, a standard of care claim generally cannot get off the ground, no matter how badly things turned out.

Element 3: Did the substandard care cause your injury?

Even if you prove the care was negligent, you must still prove the negligence caused your injury. Causation is frequently the hardest element to establish in a medical case, and where many otherwise strong claims collapse.

What is the "but for" test?

The default test for causation in Canadian negligence law is the "but for" test. You must prove, on a balance of probabilities, that but for the provider's negligence, you would not have suffered the injury. Put plainly: if the provider had met the standard of care, would you have avoided the harm? If the answer is yes, causation is established. If the harm would have happened anyway, it is not.

The leading modern statement of this test is Clements v. Clements, 2012 SCC 32. That case arose from a motorcycle crash rather than a medical error, but the Supreme Court used it to restate the causation test that applies across all of negligence law, including medical malpractice. The Court confirmed that "but for" is the default and primary test, and that a plaintiff must generally prove it to succeed. The Court also recognized a narrow exception, sometimes called "material contribution to risk," but stressed that it applies only in unusual circumstances and rarely helps in an ordinary medical case. For most patients, causation means the "but for" test.

Does causation have to be proven with scientific certainty?

No. This is where the other leading case, the medical malpractice decision in Snell v. Farrell, 1990 CanLII 70 (SCC), comes in, and it is genuinely helpful to injured patients. In Snell, an ophthalmologist continued a cataract operation after noticing bleeding behind the eye. The patient later lost vision in that eye due to optic nerve damage. The trouble was that the exact cause of the damage could not be proven with medical certainty, partly because the bleeding had obscured the very area that would have revealed the cause.

The Supreme Court held that causation need not be proven with scientific precision. It is a practical question of fact that can be answered by ordinary common sense. Importantly, where the defendant's own negligence makes it difficult or impossible for the plaintiff to prove exactly what happened, and the defendant is in a better position to know, a court may draw an inference of causation from the evidence, in the absence of persuasive evidence to the contrary from the defendant. The legal burden of proof stays on the plaintiff throughout, but the plaintiff does not need laboratory grade proof of the mechanism of injury. This "robust and pragmatic" approach prevents a wrongdoer from escaping liability simply because the science is uncertain.

Why is causation so often the hardest element?

Because medical patients are, by definition, already unwell. In a car crash, a healthy person is injured by the collision, and the cause is usually obvious. In a medical case, the patient came to the provider because something was already wrong. When the outcome is bad, the defence will almost always argue that the underlying illness, not any error, caused the harm, and that the patient would have ended up in the same place regardless.

Consider a missed cancer diagnosis. Even if you prove the doctor negligently failed to order a test, you must still prove that earlier detection would probably have changed the outcome. If the cancer was already advanced and the outcome would have been the same, causation fails even though the care was substandard. Canadian law does not compensate a lost chance of a better outcome as such; you must prove, more likely than not, that the negligence made the difference. This is why causation, not the breach itself, is frequently the graveyard of medical malpractice claims. Missed and delayed diagnosis claims raise these questions in their sharpest form, and we go deeper into them in our guide on misdiagnosis and missed cancer claims.

Element 4: Did you suffer real harm (damages)?

The fourth element is damages, meaning actual, compensable harm. Negligence that causes no injury is not actionable. If a provider made an error but you suffered no lasting harm, or the error was caught and corrected with no consequence, there is nothing to compensate and no viable claim, however unacceptable the error was.

Where there is real harm, the law tries to put you, as far as money can, in the position you would have been in had the negligence not happened. Damages fall into two broad categories. Pecuniary damages are measurable financial losses. Non pecuniary damages are for pain, suffering, and loss of enjoyment of life. The main heads include:

• Past and future loss of income. Wages and earning capacity you have lost, and will lose, because of the injury.
• Cost of future care. The cost of treatment, therapy, medication, equipment, attendant care, and support your injury will require, sometimes for life. In catastrophic cases, such as a severe brain injury, this is usually the largest head of damages by far and can run into the millions.
• Out of pocket expenses. Money already spent because of the injury, from medications to travel to appointments to home modifications.
• Pain and suffering. Compensation for the physical pain, emotional suffering, and loss of enjoyment of life caused by the injury. This head is subject to a cap set by the Supreme Court of Canada, discussed below.
• Family members' claims. Under the Family Law Act, close family members can claim for their own losses, such as the loss of the injured person's care, guidance, and companionship, and the value of nursing and housekeeping services they provide.

One point surprises many people. Pain and suffering awards in Canada are capped. In a series of 1978 decisions, the Supreme Court of Canada placed an upper limit on non pecuniary damages, adjusted for inflation ever since; for 2026 that cap sits at roughly $465,000 to $470,000. It applies to every personal injury claim, including medical malpractice, so even in the most tragic case the pain and suffering portion cannot exceed that ceiling. The truly large medical malpractice awards are driven not by pain and suffering but by future care and lost income, which are not capped. For serious lifelong injuries, our guide on spinal cord injury settlements explains how future care becomes the dominant number.

Illustrative examples: passing and failing the four gates

The following are illustrations only. They are not real clients and not predictions about any particular case. They show how the four elements play out, and why a claim can fail at any one of the four gates.

A missed fracture that leads to permanent damage (likely passes all four). A patient goes to an emergency department after a fall with clear signs of a wrist fracture. The physician misreads the x-ray and sends the patient home with a diagnosis of a sprain. The fracture goes untreated for weeks, heals badly, and leaves permanent loss of function and chronic pain that ends the patient's trade. Duty is clear. An expert says a reasonable emergency physician would have identified the fracture, so the standard was breached. Another expert says prompt treatment would probably have led to a normal recovery, so the delay caused the harm. The losses are real and permanent. All four gates are met.

A known surgical complication despite careful surgery (fails at the standard of care). A patient undergoes a properly indicated operation, consents after being warned of the recognized risks, and the surgery is performed competently. Nonetheless, one of those known risks materializes, and the patient is left with a serious complication. It is a terrible outcome. But because the surgeon met the standard of care, there is no breach, and the second gate is not passed. A bad result flowing from a known risk of competent surgery is not malpractice.

A negligent delay that changes nothing (fails at causation). A patient with an aggressive, already widespread cancer sees a doctor who negligently delays ordering a scan by several weeks. The delay is a genuine breach of the standard of care. But the medical evidence shows the cancer was incurable by the time the patient first presented, and the outcome would have been the same either way. Because the patient cannot prove that but for the delay the outcome would probably have been better, causation fails. The care was substandard, yet there is no compensable claim, which is one of the hardest lessons in this area of law.

A pharmacy error caught before harm (fails at damages). A pharmacy negligently dispenses the wrong medication, but the patient's spouse notices the label, the error is caught before a single dose is taken, and the correct medication is supplied the same day. The duty and the breach are obvious. But no one was harmed. Without an injury, there are no damages, and there is no viable claim, however alarming the mistake.

A surgical item discovered years later (passes, and shows how discoverability works). A patient has abdominal surgery and, for years afterward, suffers unexplained pain attributed to other causes. Five years later a scan reveals a surgical sponge left inside during the operation. Here all four elements can be met, and, as explained below, the two year clock generally does not start until the patient discovered, or reasonably should have discovered, that an error had caused the harm, not on the day of the surgery.

What is not medical malpractice?

Understanding what is not malpractice helps you see whether you have a real claim. Several things that feel like malpractice are not, in law.

A bad outcome, on its own, is not malpractice. Medicine carries risk, and competent care can still end in death or disability. A disagreement with your provider's judgment is not malpractice, as long as the judgment was one a reasonable provider could make. A known complication that you were warned about, and that occurred despite careful treatment, is generally not malpractice, because the risk was inherent, not the product of negligence. Rudeness or poor bedside manner is not malpractice unless it caused actual injury. And the fact that a different doctor would have done something differently is not enough. There is often more than one reasonable approach, and choosing one over another is not negligence.

There is one distinct category worth naming: informed consent. Separate from whether the treatment itself was competent, a provider generally must disclose the material risks of a proposed treatment so the patient can make an informed decision. A failure to obtain informed consent can ground its own claim, but it has its own tests and leading cases, and it turns on whether a reasonable patient, properly warned, would have declined the treatment. If your concern is that you were never told about a risk that later materialized, raise that with a lawyer specifically, because it is analyzed differently from a claim that the treatment was performed negligently.

How is a medical malpractice claim different from a car accident claim?

Many people come to a medical malpractice case having heard about Ontario's car accident rules, and they assume the same barriers apply. They do not. Medical malpractice is ordinary negligence, not auto insurance law, and that difference matters for what you can recover.

The two bold rows are the ones people find most surprising. In a car accident claim, Ontario law imposes an injury threshold and a statutory deductible that can reduce a pain and suffering award, sometimes to zero, as we explain in our guide on Ontario's injury threshold. Neither the threshold nor the deductible applies to a medical malpractice claim. If you prove the four elements, your pain and suffering award is not cut by a statutory deductible, and there is no gate that requires your impairment to be "permanent and serious" before you can recover anything at all.

That does not make medical malpractice claims easier overall. What you save at the threshold and deductible, you more than pay for at the standard of care and causation gates. But the specific auto insurance traps that catch car accident victims are not part of a medical malpractice case.

What are the deadlines to sue for medical malpractice in Ontario?

Deadlines can end a medical malpractice claim before anyone ever looks at the medicine. The limitation rules are strict, and in this area they are unusually easy to get wrong, because the harm is often hidden and because a death triggers a separate, harder deadline. The table below is the overview, and the explanation follows.

What is the basic two year limitation period?

Under section 4 of the Limitations Act, 2002, the basic rule is that you cannot start a proceeding more than two years after the day the claim was discovered. Two years is the headline number for a standard adult medical malpractice claim. But the words "was discovered" are doing enormous work, and they are what make medical limitation periods different from a simple two year countdown from the date of treatment.

How does discoverability change the start date?

Discoverability is often the most important limitation concept in a medical malpractice case. Under section 5 of the Limitations Act, 2002, a claim is discovered on the earlier of two dates: the day you first knew certain things about your claim, and the day a reasonable person in your circumstances first ought to have known them. The things you must have known are, roughly: that an injury occurred, that it was caused or contributed to by an act or omission, that the act or omission was the provider's, and that a court proceeding would be an appropriate way to seek a remedy.

Why does this matter so much in medical cases? Because patients frequently have no way of knowing that their injury was caused by negligence until long after the treatment. You may be told a bad outcome was just an unfortunate complication, and only learn that an error occurred when a later doctor or a records review reveals it. In those situations, the clock does not necessarily start on the treatment date. It can start later, when you discovered, or reasonably should have discovered, that negligence probably caused your harm.

There is an important catch. The law presumes that you knew of these matters on the day the act or omission took place, unless you prove otherwise, so the burden is on you to show that you reasonably could not have known earlier. Courts also expect you to act with reasonable diligence: if you had good reason to suspect something was wrong and did nothing to investigate, a court may find that you ought to have discovered the claim sooner. Discoverability is a shield for the genuinely unaware patient, not a licence to sit on a claim you had every reason to look into. Because it is fact specific and often contested, never assume your deadline is comfortably in the future. Have a lawyer assess it early.

What is the fifteen year ultimate deadline?

Discoverability can push the start of the two year clock later, but not forever. Section 15 of the Limitations Act, 2002 imposes an ultimate limitation period of 15 years from the day the act or omission took place. After 15 years, most claims are barred even if you never discovered them, subject to limited exceptions such as those for minors, incapable persons, and deliberate concealment. The practical message is that a very old event has a hard outer limit, and the further back the treatment, the more urgent it is to get advice quickly.

What if the injured patient is a child?

The clock works differently for children. Under section 6 of the Limitations Act, 2002, the running of the basic limitation period is suspended while a person is a minor, unless a litigation guardian has been appointed to act for them. In practice, a child's own claim usually does not begin to run until they turn 18, which is why claims for injuries at birth can sometimes be brought many years later. But there is a trap for parents: a parent's own Family Law Act claim, for their own losses, is not suspended in the same way and can expire while the child's claim is still alive. Birth related injuries have their own detailed rules, which we cover in our guide on birth injury claims and deadlines for children.

What if the patient died? The Trustee Act two year trap

This is the deadline that catches grieving families, so read it carefully. When a patient dies, the claim the deceased could have brought does not simply disappear. It survives for the benefit of the estate, but it is governed by a separate statute. Under section 38(3) of the Trustee Act, an action by an estate for a wrong done to the deceased must be brought within two years of the date of death. Full stop.

The critical difference is that this two year period runs from the date of death, and it is generally treated as a hard deadline that is not extended by the discoverability rules that apply to living claimants. A family cannot rely on discovering the negligence later to buy more time on the estate's survival claim. If two years pass from the death, the estate's claim can be lost even if the family had no idea, within those two years, that negligent care contributed to the death. This is a genuine trap, because families are grieving, records take time to obtain, and the possibility of malpractice may only surface after months of questions. If a loved one has died and you have any concern about the care, speak with a lawyer well before the second anniversary of the death. The family's own claims after a death are covered in our guide on wrongful death claims in Ontario.

Why are medical malpractice cases so hard and expensive?

Medical malpractice claims have a reputation for being among the most difficult and costly personal injury cases to run, and the reputation is deserved. Understanding why helps explain why lawyers screen these cases carefully.

They live or die on expert evidence. As ter Neuzen v. Korn makes clear, the standard of care in a technical medical matter is proven through expert opinion. You generally need a qualified expert, usually a specialist in the same field as the defendant, to review the records and say that the care fell below the accepted standard. You then often need a second expert on causation, and in a serious case further experts on damages. Each report can cost thousands to tens of thousands of dollars, and must be obtained before anyone knows whether the case will succeed.

Qualified experts are hard to find. Physicians are often reluctant to testify against colleagues, and the pool willing to do so, especially in narrow specialties, can be small. Sometimes an expert must be retained from another province, adding cost and delay.

The defence is well resourced and rarely gives up easily. Most physicians in Canada are defended by a national mutual defence organization that is very well funded and highly experienced, and hospitals carry their own insurance. These defendants do not settle weak claims to make them go away, and will fund a vigorous defence with their own experts. A plaintiff has to be prepared to match that effort.

Causation is genuinely difficult. Because patients are already ill, separating the harm caused by negligence from the harm the illness would have caused anyway is often the hardest part of the case, and the part most likely to sink it.

They take years. Between gathering voluminous records, retaining experts, examinations for discovery, and the court process, a contested case commonly takes several years to resolve.

The upside for injured patients is that reputable personal injury firms take these cases on a contingency fee basis, meaning you do not pay legal fees up front, and the firm carries the substantial cost of experts and disbursements, recovering them only if the case succeeds. That model exists precisely because these cases are too expensive for most people to fund themselves. We explain how that arrangement works, and what it does and does not cover, in our guide on how no win, no fee contingency arrangements work.

How do you protect a medical malpractice claim?

You cannot change what happened in your care, but you can protect your ability to prove it and bring a claim in time. A few practical steps help.

• Get your complete medical records. You have a right to your records. Request the full chart from every provider and hospital involved, including nursing notes, imaging, lab results, and operative reports. These records are the backbone of any medical malpractice claim.
• Write down what happened while it is fresh. Keep a dated account of the treatment, what you were told, by whom, and when, along with the names of everyone involved. Memory fades, and staff move on.
• Keep records of your losses. Track missed work, out of pocket expenses, and the tasks you now need help with. Damages have to be proven, and contemporaneous notes are persuasive.
• Be careful about signing anything or giving recorded statements. Do not sign releases or give detailed statements to an insurer or defence representative before you have advice.
• Do not delay. The two year clock, the discoverability question, the 15 year longstop, and, in a death, the Trustee Act deadline all reward acting early. Even if you are unsure whether you have a case, an early consultation preserves your options.
• Get an early legal assessment. Because these cases turn on expert opinion, a lawyer can arrange the records review and the preliminary expert input needed to tell you, realistically, whether the four elements can be met before a deadline passes.

The single most damaging mistake is waiting. Records get harder to gather, memories fade, experts have to reconstruct events from thinner material, and deadlines quietly expire, especially the unforgiving two year deadline after a death. Time is not neutral in these cases. It works against the patient.

How does a lawyer help with a medical malpractice case?

A medical malpractice claim is not a do it yourself matter. A lawyer obtains the complete records, screens the case against the four elements before large sums are spent, and locates and retains the right experts on standard of care, causation, and damages, often the hardest practical task in the whole file. A lawyer also identifies every potential defendant, from the individual providers to the hospital, and every deadline that applies, including the discoverability analysis and the Trustee Act deadline in a fatal case.

Beyond the early work, a lawyer builds the damages case, so that the full future cost of care and loss of income are proven and claimed, not left on the table. A lawyer runs the litigation against well resourced defence teams and their experts and advises on when a settlement offer is fair. Because the defence does not settle weak claims cheaply, the thoroughness of the plaintiff's preparation is often what drives a resolution.

How VC Lawyers can help

Medical malpractice claims are among the most demanding cases in personal injury law, and they are won on preparation. At VC Lawyers, we assess your situation against the four elements, obtain and review the full medical record, and work with qualified medical experts to test whether the standard of care was breached and whether that breach caused your injury. We identify every deadline that applies, including the strict two year deadline that runs from the date of death, and we build the damages case so that future care and lost income are fully captured.

We work on a contingency fee basis for personal injury clients, which means no fees unless we recover for you, and the first consultation is free. If you believe you or a family member was harmed by negligent medical care, do not try to judge the four elements on your own, and do not let a deadline decide the question for you. Contact VC Lawyers for a free consultation, or learn more about our personal injury practice.

This article is general information about Ontario law. It is not legal advice, and reading it does not create a lawyer and client relationship. Every claim turns on its own facts and medical evidence, the standard of care and causation are decided on expert opinion, and the dollar figures and deadlines can change. For advice about your situation, speak with a lawyer.

Key terms explained

• Negligence. The failure to take reasonable care, causing harm to someone the law says you owed a duty to. Medical malpractice is negligence applied to health care.
• Duty of care. The legal obligation to take reasonable care to avoid harming someone. Between a provider and a patient, it is almost always present.
• Standard of care. The level of skill and care expected of a reasonable provider in the same position. A specialist is held to the standard of a reasonable specialist.
• Causation. The link between the breach and the injury. You must prove that but for the negligence, you would not have been harmed.
• The "but for" test. The default causation test: would the injury have happened but for the provider's negligence? Confirmed as the primary test in Clements v. Clements.
• Balance of probabilities. The civil standard of proof, meaning more likely than not, or more than 50 percent. Lower than the criminal standard, but still demanding on complex facts.
• Non pecuniary damages. Compensation for pain, suffering, and loss of enjoyment of life. Capped by the Supreme Court of Canada at roughly $465,000 to $470,000 for 2026.
• Pecuniary damages. Compensation for measurable financial losses, such as lost income and the cost of future care. Not subject to the cap.
• Discoverability. The rule that the two year clock starts when you knew, or reasonably should have known, that negligence probably caused your injury, rather than automatically on the treatment date.
• Ultimate limitation period. The 15 year outer deadline that bars most claims measured from the act or omission, even if never discovered, subject to limited exceptions.
• Survival action (Trustee Act claim). The claim that survives a patient's death for the benefit of the estate. Under the Trustee Act, it must be brought within two years of the date of death.
• Contingency fee. A fee arrangement in which the lawyer is paid only if the claim succeeds, and disbursements such as expert reports are funded by the firm and recovered from the result.