Even aside from the fact that he was acting in good faith and did not cause any damage to persons or property (as acknowledged by the software vendor), the procedure used to expel him is woefully lacking. I sat on the highest student discipline tribunal at my (Canadian) university and an expulsion for non-academic reasons - which had to receive final approval from both the President and the Governing Council - would only be recommended in cases involving egregious and likely criminal misconduct and only after the courts had found merit to the allegation.
Furthermore, any student faced with potential expulsion would have been entitled to a series of quasi-judicial hearings and assistance in preparing their defence. To expel someone for non-academic reasons from a publicly-funded institution (which Dawson is) should not be taken lightly and surely never in a fashion where the accused is not permitted to present their case.
It was also really crappy cover-up strategy on the school's part. By refusing due process to Al-Khabaz and expelling him with zeroes for his last semester grades, Al-Khabaz now had nothing to lose exposing both the security flaw and the injustice to the press. If they didn't play all their cards at the same time (like putting him on probation or something), he probably wouldn't have gone public.
Furthermore, any student faced with potential expulsion would have been entitled to a series of quasi-judicial hearings and assistance in preparing their defence. To expel someone for non-academic reasons from a publicly-funded institution (which Dawson is) should not be taken lightly and surely never in a fashion where the accused is not permitted to present their case.