Israel racist and unlawful?

After three years in an Israeli prison, Palestinian Parliament Chairman Aziz Dweik, of Hamas, is set to be released after a military court of appeals rejected a request to extend Dweik's remand. Dweik is a senior Hamas official who was arrested as an accomplice in the kidnapping of Gilad Schalit. Additionally, Dweik was supposed to be key in attaining Schalit's freedom (he has been held for three years illegally, without a trial or finite sentence, and has not been granted a single visit from the Red Cross as required by international law). So, why was such an important bargaining chip released before he could be included in a deal? Simple: His sentence was up. That's all. Israeli law is allowing an accomplice to terrorism and kidnapping, a senior official of a sworn enemy, free without getting anything in return because his sentence was up. If Israel is really as racist, evil, unlawful as may claim. Why let him go at all? Why not hold him indefinitely (this is not an isolated incident, this happens all the time)?