Canterbury v. Spence, 150 U.S. App. D.C. 263, 464 F.2d 772 (D.C. Cir. 1972), cert. denied, 409 U.S. 1064 (1972)
Canterbury v. Spence is the modern cornerstone of the informed consent doctrine in medical malpractice law.
Does a physician's duty to obtain informed consent require disclosure of risks and alternatives according to a patient-centered materiality standard rather than professional custom, and is causation in informed consent measured by an objective prudent-patient test? Additionally, may the informed consent claim and related hospital negligence claim proceed without expert testimony on a professional disclosure standard?
A physician has a duty to disclose all material information that a reasonable person in the patient's position would consider significant in deciding whether to undergo a proposed treatment. Materiality turns on the nature of the proposed intervention, its risks (including probability and severity), available alternatives (including no treatment), and the likely outcomes of those alternatives. The duty is subject to narrow exceptions: (1) emergencies requiring immediate treatment; (2) situations in which disclosure would pose a substantial detriment to the patient's total care and best interests (therapeutic privilege), proven by the physician and not based on mere fear that the patient would refuse; (3) risks that are either already known to the patient or are so obvious that further disclosure is unnecessary; and (4) instances where the patient knowingly waives or declines information. To establish causation, the plaintiff must show, under an objective standard, that a reasonable person in the patient's position would have declined or chosen differently if properly informed and that the undisclosed risk materialized and caused injury. While expert testimony may be needed to identify the existence, nature, and probability of medical risks, liability for nondisclosure is not measured by professional custom and does not require expert testimony on a physician's disclosure practices.
The D.C. Circuit adopted a patient-oriented, materiality-based standard for informed consent and an objective prudent-patient causation test. It held that expert testimony on professional disclosure custom is not necessary to establish the duty to disclose material risks. The directed verdict for Dr. Spence on the informed consent claim was reversed and remanded for trial; the directed verdict on negligent surgical performance was affirmed for lack of expert proof on surgical negligence. The directed verdict for the hospital on the post-operative negligence claim was also reversed and remanded for jury consideration.
Canterbury is the foundational case in American informed consent law. It reframes the disclosure duty around patient autonomy and materiality, rather than physician custom, and sets the now-dominant objective causation test. The case clarifies that expert testimony is often needed to identify medical risks and probabilities but is not required to prove what a reasonable patient would want to know. It also delineates narrow exceptions to disclosure, cautioning against paternalistic overreach. For students, Canterbury supplies the analytic roadmap for informed consent claims: identify the material risk(s), assess the limited exceptions, analyze objective causation, and distinguish disclosure-based claims from technical malpractice that requires expert evidence on professional skill.