O’Brien v. Cunard S.S. Co.
Citation: 154 Mass. 272 (1891)
Facts
O’Brien was a passenger aboard a Cunard steamship. The ship’s surgeon was vaccinating steerage passengers; O’Brien held out her arm and received a vaccination. She later claimed she did not consent to the vaccination. The court found she had consented through her conduct.
Issue
What constitutes consent to a medical procedure, and may consent be manifested through conduct rather than express words?
Holding
O’Brien consented by holding out her arm. The surgeon was entitled to rely on objective manifestations of consent. A person cannot secretly hold a contrary intent while manifesting consent through conduct and then sue for battery.
Rule
Objective consent: Consent to a touching may be manifested by conduct as well as by words. The relevant inquiry is the objective manifestation of consent — whether a reasonable person in the defendant’s position would have understood the plaintiff to be consenting. A subjective (secret) intent not to consent does not override clear objective manifestations of consent.
Significance
- Classic case establishing the objective standard for consent in intentional tort law
- Consent is an absolute defense to battery if objectively manifested — the defendant does not need to know of any secret reservations
- Distinguished from cases of fraudulent inducement of consent (where consent is invalidated by misrepresentation)
- Illustrates that apparent consent (through reasonable interpretation of conduct) operates as a complete defense