Mohr v. Williams

Supreme Court of Minnesota · 1905 · Torts

95 Minn. 261 (1905)

Updated July 23, 2026

TortsBatteryConsentMedical treatmentunauthorized surgerymedical batterypatient consentimplied consent

Facts

Plaintiff consulted defendant, an ear specialist, about trouble with her right ear, and defendant advised an operation on the right ear after examining it. Plaintiff went to the hospital expecting surgery only on the right ear and was not informed that her left ear was diseased. After plaintiff was anesthetized, defendant examined the left ear more thoroughly, found it in worse condition than the right, determined the right ear did not need the expected operation, and instead operated on the left ear. The left-ear operation was skillfully performed and beneficial in general, but plaintiff alleged it was done without her consent and therefore constituted assault and battery.

Issue

Whether a physician may, without the patient's express consent, perform an operation on a different ear than the one authorized when the patient is under anesthesia and the physician discovers the other ear is in a worse condition. Also, whether such an unauthorized but skillfully performed operation can support a civil action for assault and battery absent malice or negligence.

Rule

Ordinarily, a physician must consult the patient and obtain consent before operating, and the physician may act only within the scope of that consent. Consent is implied only in an emergency requiring reasonably necessary treatment to preserve life or limb, or when, during an authorized operation, unforeseen conditions are discovered that, if not treated, would endanger the patient's life or health. If an operation is performed without consent and outside those justifying circumstances, the touching is wrongful and unlawful and may constitute a civil assault and battery even without proof of evil intent or negligence.

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One of 10 multiple-choice questions for this case. Pick an answer to see why.

In Milwaukee, Dana Mercer agreed in writing to let Dr. Neil Rowan remove a cyst from her right wrist. After Dana was anesthetized, Dr. Rowan concluded the right wrist did not need surgery after all, but noticed that her left wrist had a different condition he believed would benefit from immediate correction, so he operated on the left wrist instead. The procedure was skillful and improved the left wrist.

If Dana sues Dr. Rowan for battery, which is the best result?

Explanation. Ordinarily, a physician must obtain the patient's consent and may act only within the scope of that consent. Consent to one operation does not automatically extend to a different operation on another body part. If there is no emergency requiring prompt action and no dangerous unforeseen condition discovered during the authorized procedure that must immediately be addressed, the unauthorized touching is wrongful and can constitute civil battery even without malice or negligence.