[8] One significant early U.S. case, Smith v. Seibly, 72 Wn.2d 16, 431 P.2d 719 (1967), before the Washington Supreme Court, establishes precedent on the mature minor doctrine.
Because of this, Smith expressed concern that his wife might become burdened in caring for him, for their existing child and possibly for additional children.
Later, after reaching Washington's statutory age of majority, then 21, the doctor was sued by Smith, who now claimed that he had been a minor and thus unable to grant surgical or medical consent.
The Court rejected Smith's argument: "Thus, age, intelligence, maturity, training, experience, economic independence or lack thereof, general conduct as an adult and freedom from the control of parents are all factors to be considered in such a case [involving consent to surgery]."
The West Virginia Supreme Court, in Belcher v. Charleston Area Medical Center (1992) defined a "mature minor" exception to parental consent, according consideration to seven factors to be weighed regarding such a minor: age, ability, experience, education, exhibited judgment, conduct, and appreciation of relevant risks and consequences.
[20] The Supreme Court of Canada recognized mature minor doctrine in 2009 in A.C. v. Manitoba [2009] SCC 30; in provinces and territories lacking relevant statutes, common law is presumed to be applied.
The Supreme Court in 1990 (Cruzan v. Director, Missouri Department of Health) allowed that "constitutionally protected liberty interest in refusing unwanted medical treatment may be inferred" in the Due Process Clause of the Fourteenth Amendment to the United States Constitution, but the Court refrained from explicitly establishing what would have been a newly enumerated right.
[34][13] In 2009, the Supreme Court of Canada ruling in A.C. v. Manitoba [2009] SCC 30 (CanLII) found that children may make life and death decisions about their medical treatment.
In the majority opinion, Justice Rosalie Abella wrote: A "dissenting"[35] opinion by Justice Ian Binnie would have gone further: Analysts note that the Canadian decision merely requires that younger patients be permitted a hearing, and still allows a judge to "decide whether or not to order a medical procedure on an unwilling minor".