Yesterday, battery charges were dropped against a Kansas City Chiefs fan who in 2009 flipped off the surrounding fans at San Diego's Qualcomm Stadium then got into a scuffle with security who intervened. The trial court ruled that the fan, Jason Ensign, was exercising his free speech rights in flipping the bird, thus giving him the right to defend himself against the security guards who tackled him.
Deadspin is having some fun with this, but this seems like precisely the right result. Note, however, that it does not necessarily speak to the full question of fan speech at stadiums, but only of whether a fan can be arrested and charged criminally for speech at a stadium. It is not clear the result if, for example, security simply had removed Ensign from the stadium. And it does not speak to the continued validity of the league's fan-conduct policies (although I long have argued that most are constitutionally suspect).