I would like to know a bit more detail before jumping in and making accusations one way or another first.
Was he being inciteful? Where there signs to state that such Tshirts were considered provocative? If just stating your position regarding wanting peace is an arrestable offence then boy are the supeoners going to be coming thick and fast after they view all the protest rallies.
But I suspect there may be a tad more behind this than the headlines in the above post.