This movie dates back to when Vin Diesel occasionally had hair, and before he became the face of the multi-billion dollar "Fast & Furious" franchise. He plays Jackie DiNorscio, a low level mobster serving a 30 year sentence. He's offered a reduced sentence to roll on his associates in another case, but refuses to do so - and opts to defend himself as he was unimpressed by the defence lawyer who got him 30 years.
DiNorscio is uneducated and kind of obnoxious, but he's intermittently charming and funny, and he's not stupid. The movie mostly revolves around the problems (and comedy) he causes in the courtroom, with his behaviour driven by his absolute belief in "family." The biggest surprise of the film is how successfully Diesel sells the character.
Lightweight, but kind of fun.