Since DUers lie so much it is difficult to believe that it did happen. Thirty years is a long sentence. Things were a bit different back then so it could be something terrible.
In today's world, however, if he'd just been sentenced to thirty years in a blue district full of lefty judges, it could be anything from defending himself from a physical attack by a lefty approved "oppressed" individual or telling someone that he doesn't agree with murdering unborn babies. Lefty land is a sad place.