Decision making: When others can legally make decisions for you
Disabled children and youth: Decision making
When parents’ decision making powers come to an end
Care of Children Act 2004, s 28; Case:  1 NZLR 409
As with all children and young people, whether disabled or not, your parents are your guardians until you turn 18. As your guardians, they have the legal power to make major decisions about you – although the law recognises that in your teens your parents’ powers will lessen and you should be able to more and more make decisions for yourself.
Exactly when you should be allowed to make your own decisions will depend on you and your particular level of maturity. If, as a teenager, you have an impairment that affects your ability to understand and make decisions for yourself, your parents are likely to continue to play a major decision making role in your life until you turn 18. They may still play that role after that too, whether through an informal arrangement, or if they apply to the Family Court to be appointed as your “welfare guardians” (see above, “When judges and others can make decisions for you”).
Making informal arrangements for supported decision making after age 18
If your impairment continues after age 18, then depending on the nature and extent of your impairment, informal arrangements can be made where family, friends, neighbours, health professionals and so on provide you with assistance, support and information so that you can make your own decisions and communicate your decisions to others, without having to involve the courts and the legal system.
There are also more formal systems for decision making: see above and see the chapter “Decision making and powers of attorney”.
The “supported decision making” approach is endorsed by the UN Disability Convention (see in this chapter “Rights that are recognised internationally: The UN Disability Convention” and “Using New Zealand law to put in place a supported decision making approach, like a ‘circle of friends’”).