Brodders17 said:
so parents own their children. they therefor can do what they like with this possession as long as they dont negatively affect the property rights of others.
so a 10 yo cant choose to be a prostitute to buy drugs. can a 14yo? an 17yo? a 21yo? or do people of any age have to go to court to be able to make choices if their parents dont agree?
and on the final point the victims are the people likely to be hurt. but i guess if someone is killed noones property is damaged so no law is broken, unless they are a child and therefor the property of their parent.
Parents don't own their children, they have caretaker rights. That means they can't murder/maim/pimp their kid out, but they have the right of guardianship, i.e. the child lives with them under their care.
If a child has the ability to say no and run away from their parents (to avoid neglect for example) and they are capable of thinking rationally, then that would be the point at which they have gained full ownership rights to their own body. So there is no arbitrary age set to determine that, it depends on individual circumstances of people involved in any disputes. Most of the time there won't be a dispute so the courts won't be involved at all.
Your final point is false. If you drink and drive and that's it then there is no victim. If you hurt someone in the process, then that's the crime, not drinking and driving. The vast majority of cases that involve drink driving do not involve injuring anyone. The police should focus on reckless drivers, regardless of whether it is caused by drug consumption, sleep deprevation, text messaging, road rage etc.