As an adult you will end up dealing with law enforcement at one point or another and it is important to be able to conduct yourself respectably. As a minor there were very few serious negative repercussions that could be incurred when dealing with law enforcement, but in the real world there are many more things which you should be aware of.
One thing that can be extremely helpful is to have a lawyer whom you trust in case you end up in an unexpected confrontation with the law. You should consult a legal professional as to what you should or should not say and you have the right to speak to your lawyer in almost every legal situation. This simple thing can help you more than almost any other throughout adult life.
Understanding the legal code that governs a certain area will be helpful in staying on the right side of the law and knowing your rights will be beneficial should you end up on the wrong side of the law. Both of these can be found in the public domain either online or by contacting your local law enforcement agency. The more information you have available to you, the better off you will be in most cases when dealing with law enforcement.