Game crashes and bans count as leaving and will still apply the appropriately Competitive suspensions and bans. Please note, if this was your first offense, this should only be a 10-minute suspension, however repeated leaver violations will increase the suspension time and can eventually lead to a season-ban. This is done to discourage a user from attempting to play Competitive Mode more until they correct the issue that is causing them to leave games. You can learn more about this policy in detail here:
While Blizzard nor players like myself can help with the penalties we can help you identify and possibly fix the crash or freeze on your computer. Since you did not provide many details about the crash, I will refer you to this troubleshooting guide first as it helps resolve most common issues: