Some legislation allows for treatment to be given in certain circumstances without the patient's volition. For example, irresponsible people with communicable diseases may be treated against their objection, as in the case of patients with tuberculosis who are noncompliant with treatment. Also, all provinces allow for the involuntary admission of patients to psychiatric facilities, provided they present an immediate risk to themselves or others, or are unable to take care of themselves

Voluntariness is a legal requirement of valid consent. In Beausoleil v. Sisters of Charity[8] a young woman about to undergo spinal surgery repeatedly requested a general anesthetic and refused a spinal anesthetic. After the patient had been sedated, the anesthetist convinced her to have a spinal anesthetic. The patient was subsequently paralyzed as a result of the procedure and successfully sued the anesthetist. In testimony, a witness said that the patient "refused [the spinal anesthetic], but they continued to offer it to her; finally she became tired and said: 'You do as you wish' or something like that."[9] The judge stated that the patient's agreement to the spinal anesthetic was involuntary, because it rested on "words which denote defeat, exhaustion, and abandonment of the will power."