It's the effects of a motorcycle accident about 30 years ago that ripped up his face; he's never looked the same, and I suspect it's the reason for his beard.
He’s also a recovering alcoholic, so it’s an exponential function.
No offense to you as a former classmate, but I always thought he was a very strange casting choice.
No proof to base it on, but I figure either nepotism, the gay cartel or some other dynamic had to have been at play to explain why such a talentless goofball would’ be picked for that role.