Tunis — Outside the courthouse, 16 armed police officers screen all comers, including hundreds of lawyers in flowing black robes. Beyond a wall of barbed wire, a throng of bearded young men angrily shout slogans. The scene sends a clear message: Could be trouble here.

The subject of all this attention is a short, hyperactive, wise-cracking TV mogul who smokes fat stogies, has 25 bodyguards on his payroll and is on trial over charges of libeling Islam.