Our policy is we don't want guys to twitter information about our team that creates an advantage for the other team. And secondly, we monitor guys' Twitter so that they are not putting information out that could be personally damaging to them in the future in terms of the kind of information that they choose to put out there, but we don't have a policy where you can't do it.
— Coach Nick Saban from today's press conference. The issue seems to be related to Duron Carter's tweet before the game last Saturday that he wasn't going to play. That, in turn, had fueled speculation about his status. And while the policy isn't particularly surprising I had not seen it stated explicitly prior to these statements by Coach Saban.