Citizen Vigilante BANNED: Why The Honest Film Terrifies Europe (youtube.com)
What is unprecedented about this movie is that until now, whenever there was a criminal, they would swap his race to make him white (not always but sometimes), and in this film the criminals reflect stats.
Critics of the FSK, the German board that has effectively censored the film from being shown in theaters by refusing to give it any age rating, say it's because this film refused to lie that it was banned.
BP notes that among the slop produced by Hollywood, this film is refreshing, even if it doesn't aim to be anything great.