Supporting and enhancing young people's capacity for autonomy includes developing skills and attitudes that provide an understanding of what matters to the individual. Autonomy may be considered an individual matter but we are all members of a wider society and some social circumstances help us to be more autonomous and some undermine autonomy.
It is the aim of parents and educators to instil good autonomy-developing skills in children. Some children have not been given the tools, early on, to enable this development.
Teenagers in the care system sometimes disagree with the views of their court-appointed guardian and may be deemed competent to give their own instructions to their lawyer. Many have a highly developed sense of their own self-worth, interests, values and attitudes and are able to choose well for themselves and challenge factors that undermine autonomy
The case of Re: Q as it sets out the position for 17 year olds and [interim] care/supervision orders and recognises "the growing autonomy of the individual child"
No interim care order or interim supervision order can persist after a child's 17th birthday (or 16th birthday if married) ... In the event that a child aged 17 (or married aged 16 or over) is presently placed in the care of a local authority or under the supervision of a local authority under an interim order that order is, in fact, ultra vires and cannot stand