In Arizona are you automatically emancipated at age 18?

No... emancipation is the process of an underage child (17 and under) proving to the state they live in that they are self sufficient and can support themselves. The court must determine (by a number of factors) that the child can financially and emotionally provide for themselves. They consider if you:

-have a job

-have finished school or are attending regularly

-have future plans for yourself

-have good reason to be on your own without adult supervision

-have a criminal background of any kind

-have a good reason to leave the situation you are in

-and more

If the court determines you have good cause and can support yourself, they may then emancipate you, giving you most rights that an adult would have (not buying cigarettes and/or alcohol, etc.).