Ontario Professional Negligence — Duty, Standard of Care, and Damages

The Professional Negligence Framework

Professional negligence is a subspecies of the tort of negligence, applying when a person holding themselves out as possessing special skill or knowledge provides services below the standard reasonably expected of a competent member of that profession. The plaintiff must establish the classic negligence elements: (1) duty of care; (2) standard of care; (3) breach; (4) causation; and (5) damages.

The Anns/Cooper test governs duty of care in Canadian negligence law (Cooper v Hobart [2001] 3 SCR 537): (1) is there a sufficiently close relationship between the parties from which a prima facie duty arises (foreseeability + proximity)? (2) Are there policy reasons to negate or limit the duty? For established professional relationships — solicitor-client, physician-patient, architect-client — the duty is not in dispute. Novel duty situations require full Anns/Cooper analysis.

The standard of care in professional negligence is objective: the court asks what a reasonably competent member of the relevant profession, with the defendant's level of specialization, would have done in the same circumstances. This is not a perfection standard — errors in judgment do not constitute negligence if they represent choices a reasonable practitioner could make. Expert evidence on the standard of care is almost always required.

Solicitor Negligence

Solicitor negligence is one of the most litigated areas of professional liability in Ontario. The solicitor-client relationship creates a duty of care in both contract and tort (Central Trust Co v Rafuse [1986] 2 SCR 147 — concurrent liability). The Limitations Act 2002 two-year period runs from the date the client knew or ought to have known of the damage, not from the date of the negligent act.

Common categories of solicitor negligence:

• •Limitation period failures — missing the 2-year Limitations Act period or 10-day discovery deadline under the Proceedings Against the Crown Act is the leading category of LAWPRO claims. No "mistake" defence — a limitation miss is strict liability negligence.
• •Title defects in real estate — failure to search title, missed executions, survey errors, failure to obtain title insurance where appropriate. Krawchuk v Scherbak 2011 ONCA 352 — solicitor liable for failing to advise on survey discrepancy.
• •Trust accounting errors — misappropriation (no defence), misapplication of trust funds, failure to remit to correct party, delayed payment. LAWPRO indemnity does not cover deliberate misappropriation.
• •Inadequate advice — failure to advise on tax consequences, failure to identify legal issues, failure to recommend independent legal advice in conflict situations, failure to advise on risks of proceeding.
• •Document drafting errors — wills (failure to execute, missing attestation, capacity, undue influence), agreements of purchase and sale (conditions, closing dates), commercial contracts (missing conditions precedent, no limitation of liability).
• •Undertaking breaches — undertakings given to other solicitors are enforceable as solicitor obligations; failure to fulfill creates professional misconduct and civil liability.

Causation in solicitor negligence: the "but for" test (Athey v Leonati [1996] 3 SCR 458). For litigation file failures, the plaintiff must prove they had a "viable" or "good arguable" case (Hall v Bennett Estate 2003 ONCA — not certainty of success). The court conducts a "trial within a trial" to assess the lost chance. For transactional negligence, the plaintiff must show what they would have done differently with proper advice (often "I would not have entered the transaction").

LAWPRO (Lawyers' Professional Indemnity Company) is the mandatory insurer for Ontario lawyers. Coverage: $1 million per claim for most lawyers; $2 million aggregate per year. TitlePLUS program for real estate. Coverage exclusions include fraudulent acts (though innocent partner coverage exists), business enterprise activities, and claims between law firm partners/employees.

Medical Negligence

Medical negligence in Ontario follows the same negligence framework with profession-specific standards of care. The physician's standard of care is that of a reasonably competent physician in the same specialty in the same or similar circumstances — a cardiologist is held to a cardiologist's standard, not a GP's standard (ter Neuzen v Korn [1995] 3 SCR 674).

Informed consent is a separate head of liability distinct from negligence in the performance of the procedure. Under Reibl v Hughes [1980] 2 SCR 880, the standard for disclosure is objective-subjective: what information would a reasonable patient in the plaintiff's circumstances want to know, assessed against the specific patient's circumstances and questions asked. The physician must disclose material risks — those that a reasonable person in the patient's position would want to know. Causation for informed consent: would the patient have refused the procedure if properly informed? This is assessed objectively — not whether this particular plaintiff would have refused, but whether a reasonable person in the plaintiff's position would have refused (modified objective standard from Arndt v Smith [1997] 2 SCR 539).

Causation in medical negligence: general but-for test (Athey), with material contribution to risk exception where multiple defendants may each have contributed and it is impossible to determine which caused the harm (Clements v Clements [2012] 2 SCR 181 — material contribution to risk applies only where but-for would deny recovery to a plaintiff who was clearly injured by a defendant's breach).

Limitation periods: standard 2-year Limitations Act 2002 discovery-based period, with the 15-year ultimate limitation period under s.15. For children, the limitation period does not run until the child reaches age 18 (s.6). For claims arising from sexual abuse, special rules under s.10 (no limitation period for certain claims).

Architect and Engineer Liability

Architects and engineers owe a duty of care to their clients in both contract and tort. The standard of care is that of a reasonably competent practitioner in the relevant specialty. Design errors, supervision failures, and certification errors are common categories of claims.

Under the Construction Act RSO 1990 c C.30, certified progress payment certificates (Form 9 architect's certificate) bind the certifier — an architect who certifies work as complete when it is not can face liability to the owner. The architect's duty to the owner includes inspecting construction for substantial compliance with drawings and specifications.

Third party liability: under Hedley Byrne principles (adopted in Canada inHaig v Bamford [1977] 1 SCR 466), a professional may owe a duty to third parties who reasonably rely on their work product if the professional knew the statement or report would be communicated to a limited class of persons for a specific purpose. Environmental assessors, appraisers, and structural engineers may face third-party liability to purchasers who relied on their reports.

Auditor and Accountant Liability

Auditors owe a duty to the audited company and its shareholders as a class. Third-party claims by creditors and investors who relied on audit reports are governed by theHercules Management Ltd v Ernst & Young [1997] 2 SCR 165 framework: duty of care to the class of shareholders as a group for the purpose of supervising management, but NOT to individual shareholders making investment decisions or to third-party lenders.

Standard of care for auditors follows GAAP and GAAS (Generally Accepted Auditing Standards). Failure to detect a material misstatement may constitute negligence if a competent auditor applying GAAS would have detected it. Fraud by management is not generally attributable to auditor negligence unless the auditor failed to apply appropriate skepticism required by auditing standards.

Ontario Securities Act Part XXIII.1 secondary market civil liability: auditors who certify financial statements included in a prospectus or annual report face statutory liability for misrepresentations. This is a form of securities professional liability distinct from the tort of negligence, with different causation and damages rules.

Defences and Contribution

Contributory negligence under the Negligence Act RSO 1990 c N.1: where the plaintiff's own negligence contributed to their damage, liability is apportioned proportionately. Contributory negligence is commonly raised in professional negligence — "the client failed to read the contract and would have identified the defect."

Voluntary assumption of risk (volenti non fit injuria): the plaintiff knew of and agreed to accept the risk. Rarely succeeds in professional negligence — courts are reluctant to find a client assumed the risk of professional incompetence.

Contractual limitation of liability: professionals may limit their liability by contract to a fixed amount or to fees paid. Courts will enforce limitation clauses if clearly expressed and not unconscionable, though they will not enforce clauses that purport to exclude liability for fraud or intentional wrongdoing.

Concurrent tortfeasors: under the Negligence Act, multiple defendants who caused the same indivisible damage are jointly and severally liable. Contribution between professionals is assessed proportionately. A plaintiff can pursue any or all defendants for full recovery, leaving contribution claims between the defendants.

Limitation Periods — Professional Negligence

Practical Checklist for Professional Negligence Counsel

• ✓Identify the retainer or engagement scope — the professional's duty is limited to the scope of the retainer; acts outside retainer may not create liability
• ✓Obtain expert evidence on standard of care — courts will not accept counsel argument on what a "reasonable" professional would do without expert support
• ✓Apply but-for causation rigorously: what would plaintiff have done with proper advice? For litigation claims, assess lost-chance value
• ✓Check discovery: limitation runs from when plaintiff knew (or ought to have known) loss was occasioned by the professional's act — not from the act itself
• ✓Identify all potential defendants: firm plus individual practitioner; supervisors if applicable; consider contribution claims against other professionals involved
• ✓Assess contributory negligence: did the client fail to read documents, provide incorrect information, or ignore warnings? Proportionate reduction may apply
• ✓Review the professional's insurance: LAWPRO for lawyers (mandatory), CMPA for physicians, professional liability insurance for accountants/engineers/architects
• ✓For solicitor claims: file a LAWPRO claim notice early — LAWPRO defence counsel will appear; consider whether client's interests and LAWPRO's interests are aligned