Editing Informed consent (section)

===Competency of the patient===
{{unreferenced section|date=January 2023}}

The ability to give informed consent is governed by a general requirement of competency. In common law jurisdictions, adults are presumed competent to consent. This presumption can be rebutted, for instance, in circumstances of mental illness or other incompetence. This may be prescribed in legislation or based on a common-law standard of inability to understand the nature of the procedure. In cases of incompetent adults, a [[health care proxy]] makes medical decisions. In the absence of a proxy, the medical practitioner is expected to act in the patient's best interests until a proxy can be found.

By contrast, '[[Minor (law)|minors]]' (which may be defined differently in different jurisdictions) are generally presumed incompetent to consent, but depending on their age and other factors may be required to provide [[Informed assent]]. In some jurisdictions (e.g. much of the U.S.), this is a strict standard. In other jurisdictions (e.g. England, Australia, Canada), this presumption may be rebutted through proof that the minor is 'mature' (the '[[Gillick competence|Gillick standard]]'). In cases of incompetent minors, informed consent is usually required from the parent (rather than the 'best interests standard') although a [[parens patriae]] order may apply, allowing the court to dispense with parental consent in cases of refusal.