à-vis their decisional capacities and need for confidentiality in medical care and research . Furthermore, it is important to recognize that while this sets out a bright-line distinction between legal attainment of “competence” in medical decision making (as an adult), who is or is not a “child” for purposes of federal research regulation references state laws (but not specifically the age of majority) on this matter. The latter, in turn, set forth conditions under which certain “minors” might be able to make medical decisions on their own on the basis of certain life events or in certain medical scenarios. Hence, they might be “minors” according to a brightline test but are not subject to federal research regulations as “children” when state law is applied.
In the sections that follow, which discuss emancipation, the mature minor rule, and minor consent to treatment provisions, it should be emphasized that state laws have relevance in two different ways: the application of the definition of “children” and the waiver of parental permission to medical treatment and in other contexts. That is, certain state laws place a minor outside the definition of children (which would seemingly make Subpart D of the federal regulations inapplicable); other state law provisions support the waiver of parental permission (which would be much more context sensitive and which may or may not reasonably extend to research-related decisions).
As noted earlier, certain life events remove minors from the purview of child or adolescent medical regulation. That is, the age of majority may not be met, but emancipation frees the former “child” from parental custody and control. Typical conditions that states use to establish emancipation are marriage , military service , or court order  (Table B.3).
The concept of emancipation arose in common law (court-developed law) and has only more recently been explicitly addressed in statutes.5 The “classical” definition of emancipation under the common law could be summarized thusly: emancipation occurs when a minor voluntarily lives independently of his or her parents (whether by marriage, military service, or the establishment of financial independence), the latter who, in turn, make no attempt at ongoing control or care of their child. In turn, it does not seem to make sense to treat “children” who meet the common-law definition of emancipated minors as being under parental authority .