Leaver Buster makes no distinction between the client crashing and a player leaving intentionally because players could easily force the client to crash to take no penalty. There's just no way to reliably determine the cause and prevent heavy abuse of such leniency.
If you're having crash issues, you'll want to head over to the Bug Splat & Game Crashes guide for troubleshooting. You can test this in Custom games if your issue persists. If you need further assistance, please post on the Help & Support board and they'll do what they can to help you further.
If the issue persists, continuing to queue up for matches is irresponsible because it ruins the match for your team whether it's intentional or not. Help us help you so you can go back to playing matches without worrying about low priority queues and lost games and angry teammates.