Funny. Article 38 of the Constitution states: They [the members of parliament] are representatives of the whole people, not bound by orders and instructions and subject only to their conscience - I can't find anything about party discipline there. Interesting too is Article 21, which states: Their [the parties'] internal order must conform to democratic principles - has the suppression of dissenting opinions recently become considered a democratic principle? It must have snuck in somehow when I wasn't looking ... At RP-Online: Politik I found the original article.