As minors by law children do not have autonomy or the right to make decisions on their own for themselves in any known jurisdiction of the world. Instead their adult caregivers, including parents, social workers, teachers, youth workers, and others, are vested with that authority, depending on the circumstances. Some believe that this state of affairs gives children insufficient control over their own lives and causes them to be vulnerable. Louis Althusser has gone so far as describe this legal machinery, as it applies to children, as "repressive state apparatuses". Structures such as government policy have been held by some commentators to mask the ways adults abuse and exploit children, resulting in child poverty, lack of educational opportunities, and child labor. On this view, children are to be regarded as a minority group towards whom society needs to reconsider the way it behaves. Researchers have identified children as needing to be recognized as participants in society whose rights and responsibilities need to be recognized at all ages. In law, a minor is a person under a certain age — usually the age of majority — which legally demarcates childhood from adulthood; the age depends upon jurisdiction and application, but is generally 18. "Minor" may also be used in contexts not connected to the overall age of majority; for example, the drinking age in the United States is 21, and people below this age are sometimes referred to as "minors" even if 18. The term underage is often
used to refer to those under the age of majority, but may also refer to persons who are under a certain age limit, such as the drinking age, smoking age, age of consent, marriageable age, driving age, voting age etc., with these age limits often being different than the age of majority. The concept of "minor" is not sharply defined in most jurisdictions. The ages of criminal responsibility and consent, the age at which attendance at school ceases to be obligatory, the age at which legally binding contracts can be entered into, and so on, may all be different. In many countries, including Australia, India, Philippines, Brazil, Croatia and Colombia, a minor is defined as a person under the age of 18. In the United States, where the age of majority is set by the individual states, minor usually refers to someone under the age of 18, but can in some states be used in certain areas (such as gambling, gun ownership and the consuming of alcohol) to define someone under the age of 21. In the criminal justice system in some places, "minor" is not entirely consistent, as a minor may be tried and punished for a crime either as a "juvenile" or, usually only for "extremely serious crimes" such as murder, as an "adult". In Japan, Taiwan, and South Korea, a minor is a person under 20 years of age. In New Zealand law, a minor is a person under 20 years of age as well, but most of the rights of adulthood are assumed at lower ages: for example, entering into contracts and having a will are legally possible at 15.