Pleading guilty to computer hacking at 17 is a very serious matter. Not like staying up past your bedtime, or pranks like smashing pumpkins and streaking around the block when you're 14. Hacking goes to your honesty, integrity, and trustworthiness. If you really want to become a licensed attorney, an officer of the court, you'll wait for the Bar Association to uncover your past at your peril. Even if you slid it under the radar to get the license to practice law, how do you know that somebody who remembers you wouldn't inform the Bar Association upon learning that you, former computer hacker, had become an attorney? You might find yourself disbarred for offering a fraudulent application. Best to disclose it up front. It's a hell of a lot easier to explain your conduct at 17 when you're forthcoming about it than it is to explain away why you weren't forthcoming about it in the first place.
any bar association person or lawyer says when in doubt disclose...This exact situation is asked in MPRE questions and the answer is always disclose.