Medical malpractice in Canadian common law requires expert evidence to establish the standard of care, the breach of that standard, and (typically) causation. The general rule, articulated by the Supreme Court of Canada in ter Neuzen v Korn, [1995] 3 SCR 674, reflects the specialized nature of clinical practice — what counts as a breach of the standard for any particular procedure or intervention is generally not within the experience or knowledge of lay people. The rule has a narrow exception, recognized as far back as Anderson v Chasney, [1949] 4 DLR 71 (SCC): where the alleged negligence is “plainly obvious” to a lay person — the classic example being a surgical sponge left in a wound — expert evidence may not be required. The exception operates only where the carelessness is obvious without specialized medical knowledge.
Rybakov v Khattak, 2024 BCCA 96, is the Court of Appeal for British Columbia’s recent application of these foundational rules. A patient who had received a course of electroconvulsive therapy (ECT) alleged that the treating psychiatrists had breached the standard of care by increasing the electrical charge and duration of the ECT stimulus across several sessions without disclosing the increases to him. He proceeded to a jury trial. At the close of the plaintiff’s evidence, the trial judge dismissed the action because no expert evidence had been tendered to establish the standard of care. The Court of Appeal dismissed the appeal: the case fell squarely outside the Anderson v Chasney exception; expert evidence was required; and the trial judge was right to dismiss before the jury deliberated.
The case is doctrinally significant because it engages four frameworks together: the expert evidence requirement, the Anderson v Chasney exception, the non-suit doctrine as it operates mid-trial, and the implicit standard for ongoing disclosure during a course of treatment.
The clinical context: electroconvulsive therapy
Electroconvulsive therapy is a psychiatric treatment in which a brief controlled seizure is induced through electrical stimulation of the brain. The treatment is delivered under general anesthesia and muscle relaxant. The therapeutic objective is a seizure of adequate duration (typically more than 15 seconds) and quality to produce neurochemical effects that improve symptoms of severe psychiatric illness.
ECT is established treatment for several conditions: severe depression unresponsive to medication or where treatment urgency is high (catatonia, severe suicidal ideation, refusal to eat); some forms of mania; postpartum psychosis; and certain other neuropsychiatric presentations. Modern ECT, properly administered, is regarded as safe and effective. Cognitive side effects — typically memory difficulties — are common but often transient. The reputation of the treatment in popular culture is more troubled than the clinical evidence supports, although patient concern about ECT is widespread and well-documented.
A course of ECT typically involves several sessions over a period of weeks. The “dose” — the electrical charge measured in millicoulombs and the pulse parameters — is titrated across the course. Increased dose may be required to maintain seizure quality and therapeutic effect as the patient progresses. Dose adjustment is part of competent ECT practice.
Patient vulnerability is a relevant clinical consideration. ECT patients by definition have severe psychiatric illness. Many are in acute distress; some lack full capacity at certain points in their treatment; some have understandable apprehension about the procedure. Communication standards in ECT practice are correspondingly heightened, with significant attention to ensuring that the patient understands and remains willing to continue the treatment.
The substantive case
The plaintiff had received a course of ECT under the care of the defendant psychiatrists. During the course, the psychiatrists increased the electrical charge and the duration of the stimulus on various occasions. The increases were not communicated to the plaintiff.
The plaintiff alleged that the failure to disclose the dose adjustments was a breach of the standard of care. He brought the action against the prescribing and administering physicians and elected jury trial.
At trial, the plaintiff did not tender expert evidence. There was no psychiatrist who had testified that the standard of care for ECT practice required disclosure of dose increases at each session, or that the practice of adjusting dose without notification was below the practising standard of care. Without that evidence, the plaintiff was asking a lay jury to determine whether the conduct fell below the standard for psychiatric practice — without anyone qualified to tell them what that standard was.
The non-suit at trial
At the close of the plaintiff’s evidence, the trial judge dismissed the action. This is the non-suit framework operating mid-trial. The test is whether the plaintiff’s evidence, taken at its highest and most favourable to the plaintiff, is sufficient to support a verdict in the plaintiff’s favour. Where the evidence is insufficient on a necessary element of the cause of action, the trial judge can dismiss without sending the case to the jury.
In a medical malpractice case where expert evidence is required, the absence of expert evidence is by definition a fatal evidentiary gap. The plaintiff cannot meet the standard of care element without expert testimony about what the standard is and how it was breached. A lay jury cannot supply the gap by exercise of common sense, because the standard of care for specialized clinical practice is not common sense.
The trial judge’s mid-trial dismissal recognized this. The plaintiff’s case had concluded without putting forward the expert evidence required to support the alleged breach. No reasonable jury, properly instructed on the law, could find a breach of the standard of care on the evidence before it.
The appellate analysis: expert evidence required
The Court of Appeal for British Columbia affirmed.
The court began with the general rule: medical malpractice requires expert evidence to establish the standard of care. The rule is grounded in the specialized nature of clinical practice. The court then turned to the Anderson v Chasney exception: where the alleged negligence is plainly obvious to a lay person, expert evidence may not be required.
The court applied a structured analysis. The exception applies where:
- A particular risk has materialized to which the plaintiff was exposed
- The risk could have been avoided by obvious and reasonable precautions, OR
- The defendant’s practice was fraught with foreseeable risk
The court found neither of these on the record. There was no evidence at trial that any particular risk had materialized — no evidence, for example, that the dose increases had caused harm that disclosure would have avoided. There was no evidence that the practice of not disclosing dose increases was inherently dangerous or fraught with foreseeable risk.
The court explicitly acknowledged what expert evidence might have established. The court considered that a properly qualified expert might have testified that:
- Changes in charge and duration of ECT ought to be communicated to the patient even in the absence of material risk
- The vulnerability of ECT patients requires communication of all treatment-related facts at each session
- The accepted practice among psychiatrists administering ECT includes ongoing disclosure of routine treatment information
The court’s point was not that no such standard exists. The court’s point was that establishing such a standard on the evidence at trial required expert testimony. Without it, the jury was being asked to determine the standard by reference to the lay common sense of jurors with no expertise in psychiatry, ECT, or the communication norms of either. The standard for psychiatric practice is not a matter of lay common sense, and the Anderson v Chasney exception does not extend to cases where the standard is at issue rather than the obvious carelessness.
There was also no expert evidence on causation. The court noted this separately. Even if SOC could have been established, the plaintiff would have needed expert evidence to demonstrate that the alleged breach (failure to disclose) was the cause of the harm complained of. The absence of causation evidence was a separate, independent reason why the action could not succeed.
The implicit informed consent angle
The substantive allegation in Rybakov is in the family of informed consent claims. The plaintiff was effectively alleging that the physicians had not adequately informed him of changes during the course of his treatment. This implicates the Reibl v Hughes, [1980] 2 SCR 880, framework as it operates in ongoing treatment.
Reibl addresses the disclosure required for initial consent — what risks must be disclosed before a procedure begins to allow informed consent or refusal. The framework operates on a single moment of disclosure: the consent conversation.
Many treatments, however, involve ongoing rather than single-point decisions. A course of ECT, like a course of chemotherapy or a long-term medication regimen, requires repeated decisions about whether to continue, modify, or stop. The question of how the disclosure framework operates in ongoing treatment is somewhat undertheorized in Canadian law. Rybakov implies the answer: where ongoing treatment is at issue, expert evidence is generally required to establish what continuing disclosure the standard requires. The standard may well include ongoing disclosure of dose adjustments — particularly in vulnerable patient populations — but establishing the standard requires the testimony of psychiatrists who can speak to actual practice and to the norms of the relevant clinical community.
The takeaway for plaintiff counsel: framing a disclosure claim as informed consent and asking the court to apply Reibl directly is not enough. The expert evidence must address the ongoing disclosure standard specifically. The Reibl framework provides the doctrinal architecture, but the substantive content of the disclosure obligation in ongoing treatment requires expert input.
The doctrinal lessons
The case stands for several propositions.
Expert evidence is the rule. Medical malpractice cases require expert evidence on standard of care, breach, and typically causation. The rule reflects the specialized nature of clinical practice. Plaintiffs proceeding without expert evidence face structural obstacles that the common-law framework will not relieve.
The Anderson v Chasney exception is narrow. Where the alleged negligence is plainly obvious to a lay person, expert evidence may not be required. The exception operates only in cases of obvious carelessness — the surgical sponge, the obvious failure to attend, the patently inappropriate medication. It does not extend to disputes about the standard of care for specialized practice, even where the underlying narrative (X happened, Y did not happen) can be described without specialized knowledge.
Mid-trial dismissal is available. Where the plaintiff’s evidence at trial is insufficient on a necessary element of the cause of action, the trial judge can dismiss without sending the case to the jury. The non-suit framework operates as a procedural safeguard against verdicts founded on inadequate evidence.
Ongoing disclosure requires its own framework. The Reibl v Hughes informed consent framework operates at initial consent. The standard for ongoing disclosure during a course of treatment requires its own expert testimony. Plaintiff counsel framing a disclosure claim about ongoing treatment must marshal expert evidence on the specific ongoing-disclosure standard, not assume Reibl will fill the gap.
Patient vulnerability is a relevant factor. The Court of Appeal noted that the vulnerability of ECT patients might support a more demanding disclosure standard. This is a useful doctrinal observation. In other vulnerable patient populations (cognitively impaired patients, minors, patients receiving intensive care), the standard for ongoing communication may also be heightened. Expert testimony can develop the doctrine in specific contexts.
Causation evidence is also required. Even where SOC can be established, the plaintiff must prove causation on a balance of probabilities. The Clements v Clements, 2012 SCC 32, but-for test typically requires expert evidence in malpractice cases. The plaintiff in Rybakov did not tender causation evidence either; this was a separate, independent ground for dismissal.
Comparison: Rybakov and Beazley
Rybakov v Khattak sits alongside Beazley v Johnston, which I rewrote earlier in this project. The two cases produce similar outcomes for related but distinct reasons:
- Beazley v Johnston (Ontario summary judgment): the plaintiff tendered expert evidence, but the expert was disqualified at the White Burgess Langille Inman v Abbott and Haliburton Co, 2015 SCC 23, qualification stage. Without a qualified expert, no genuine issue for trial; summary judgment for the defendant.
- Rybakov v Khattak (BC non-suit): the plaintiff tendered no expert evidence at all. The trial proceeded but no expert testified on standard of care or causation. Mid-trial dismissal; appeal dismissed.
Both cases illustrate the structural importance of expert evidence in malpractice litigation. Beazley shows what happens when expert evidence is offered but the expert fails White Burgess qualification. Rybakov shows what happens when expert evidence is not offered at all. The outcomes are the same: dispositive dismissal without a substantive trial on the merits.
The appellate cases cluster
Rybakov v Khattak is the fifth case in the rewritten appellate cluster on this site, and the second BC appellate decision:
- Willick v Willard (Court of Appeal for Ontario): affirmance with deferential review; reasons doctrine; SOC met by both defendants
- Hanson-Tasker v Ewart (Court of Appeal for British Columbia): affirmance; competing experts displaced Snell v Farrell adverse inference; deferential review of discretionary findings
- Dumesnil v Jacob (Manitoba Court of Appeal): new trial ordered; trial judge’s SOC analysis was wrong as a matter of law
- Penate v Martoglio (Court of Appeal for Ontario): new trial ordered; inadequate reasons for jury discharge + Cojocaru verbatim copying
- Rybakov v Khattak (Court of Appeal for British Columbia): affirmance; expert evidence requirement + non-suit dismissal
The five cases cover the substantive appellate outcomes in malpractice practice: affirmance on deferential review with adequate reasons (Willick); affirmance on causation/expert evidence (Hanson-Tasker); intervention on substantive error of law (Dumesnil); intervention on procedural defects (Penate); and affirmance on expert evidence requirement (Rybakov).
The BC sub-cluster: seven cases
Rybakov v Khattak is the seventh British Columbia case in the cross-province sub-cluster:
- Massie v PHSA: class action certification
- Sheoran v IHA: physician suing hospital after patient assault
- Gilmore v Love: birth injury (skull fractures, real-time informed consent)
- Lal v Anderson: procedural (jury notice)
- Hanson-Tasker v Ewart: appellate (kernicterus causation)
- A.G. v Rivera: birth injury (preterm risk counselling, patient refusal doctrine)
- Rybakov v Khattak (this case): psychiatry / ECT, expert evidence requirement, appellate affirmance
The BC sub-cluster now provides the most comprehensive single-province coverage in the library, spanning class actions, intentional torts, birth injury (term and preterm), procedural matters, appellate decisions, and psychiatry. For BC malpractice practice generally, the seven-case set is a useful reference.
The broader cross-province sub-cluster now spans six provinces and thirteen cases.
The expert evidence cluster
Rybakov joins a substantial expert evidence cluster on this site:
- Paul’s OTLA Litigator article on expert witness qualification (framework anchor)
- Beazley v Johnston: summary judgment after White Burgess expert qualification failure
- Hanson-Tasker v Ewart: competing experts displace Snell v Farrell inference
- Knight v Lawson: qualified experts but causation defeat
- Tripp v Ross: oncology causation expert analysis
- Sutherland v Booth: plaintiff expert didn’t survive cross-examination
- 2023 in Review SRL: structural failure of SRL malpractice cases for absence of experts
- Rybakov v Khattak (this case): no expert evidence tendered; mid-trial dismissal affirmed on appeal
The cluster now provides comprehensive coverage of the expert evidence requirement and its various failure modes (qualification failure under White Burgess; cross-examination unravel; absence of testimony altogether). For prospective clients and the bar, this is a useful reference set on the structural importance of expert evidence in malpractice litigation.
Why this case matters
For prospective clients. A medical malpractice claim in Canada requires expert evidence to succeed. Without a qualified expert who is prepared to testify that the treatment fell below the standard of care, the case will not survive trial. The cost realities of retaining qualified experts mean that some claims are not economically viable for either contingency-fee or self-funded litigation. This is part of the candid evaluation that should occur at the outset, not after extensive investment in litigation that ultimately cannot succeed. See Suing for Medical Malpractice in Ontario: What You Need to Know for the broader framework.
For plaintiff counsel. Rybakov is a useful precedent on the limits of the Anderson v Chasney exception. Even where the narrative seems amenable to lay understanding (“X happened; the patient was not told”), the question of whether X falls below the standard of care typically requires expert testimony. Counsel evaluating a case for the Anderson v Chasney exception should consider carefully whether the alleged carelessness is genuinely obvious without specialized medical knowledge — and should be cautious about proceeding without expert evidence on that judgment. The mid-trial dismissal in Rybakov shows the consequences of misjudging.
For defence counsel. The case is useful precedent on mid-trial non-suit applications. Where the plaintiff has completed evidence without putting forward expert testimony required by the standard of care framework, the non-suit application is the appropriate procedural mechanism. The Court of Appeal in Rybakov affirmed the trial judge’s discretion to dismiss before jury deliberation.
For practising psychiatrists and other clinicians providing ongoing treatment. The case is a doctrinal observation about ongoing disclosure during a course of treatment. The Reibl informed consent framework operates at initial consent. The standard for ongoing disclosure is less clearly articulated in Canadian law. The Court of Appeal in Rybakov observed that expert evidence might have established a more demanding standard for ECT specifically — particularly given patient vulnerability. The doctrinal point: ongoing disclosure norms can be a relevant standard-of-care issue, and clinicians should be attentive to their practice in this area regardless of whether Reibl speaks directly to the situation.
For more on expert evidence in malpractice cases, see Paul’s article on expert witness qualification. For more on summary judgment as an expert-evidence-defeat mechanism, see Beazley v Johnston: Summary Judgment in an Expert-Qualification Case and Thorburn v Grimshaw: Summary Judgment in an Informed Consent Case.
Decision Date: March 5, 2024
Jurisdiction: Court of Appeal for British Columbia
Citation: Rybakov v Khattak, 2024 BCCA 96 (CanLII)
Key authorities: Anderson v Chasney, [1949] 4 DLR 71 (SCC) (plainly obvious negligence exception); ter Neuzen v Korn, [1995] 3 SCR 674 (expert evidence requirement); Reibl v Hughes, [1980] 2 SCR 880 (informed consent); White Burgess Langille Inman v Abbott and Haliburton Co, 2015 SCC 23 (expert qualification); Clements v Clements, 2012 SCC 32 (but-for causation)
