If the concept and rules of plagiarism is alien to a man by the time he’s in post-grad schooling... I’d think the real investigation should be in how he got into the program.
Did he earn his initial degree or did he copy off others then too?
Good point. The academic rigor of his instructors and department advisors might also be a fruitful avenue of inquiry. I’m betting it would reveal a bunch of third-string bozos handing out degrees like crackerjack prizes.
Dittos.
Anybody who is ignorant of the meaning of word “plagarism” is not worthy of an advanced degree (or even an undergrad degree for that matter).