While in Austria the promotion of national socialism is forbidden by a constitutional law, the “Verbotsgesetz” of 1947, in Germany the jurisprudence is concerned to get in conflict with the concept of freedom of speech at this point. Nevertheless the need of incrimination of NS propaganda isn`t questioned. The main way to bring criminal law in use to fight nazis is to forbid their symbols. This leads to the strange situation, that it is allowed to call oneselve national socialist, to promote the ideas, as long as you don`t use the symbols of any NS organization, like the swastika or the SS symbol or certain slogans.
This concept pretends to be neutral, which it can`t be, as its goal is to fight NS. This kind of neutral point of view is dishonest. Even the European Convention of Human Rights (ECHR) is allowing restrictions of the freedom of speech, if they are necessary for a democratic society. Sure, this kind of of restrictions should be used with care, but what could be more against the ideas of a democratic society than NS propaganda. restricting is more honest than pretending to be neutral, where you can`t be.
In latest times the german authorities are using the law against NS symbols against those, who use them for express their refusal of NS. States prosecutors in Baden-Würtemberg prosecuted a punk label for using a crossed out swastika. The court followed, as many politicians expressed their disfavor, like the federal minister for justice Brigitte Zypris, who wanted to change the law, if this interpretation of law would last.

Meanwhile some other similar cases appeared. crossed out swastikas are banned from many manifestation of the antifascist left. And even another usage of NS symbols are incriminated: a sticker is showing a street of Dresden during the NS flagged with swastikas to illustrate the role of the city in the NS and counter the myth of the innocent city, bombed at the end of the second world war.
So the attempt to ban NS propaganda without taking any point of view leads to a situation, where the history is just wiped out. You are not allowed any more to show the reality of NS. thats absurd. I still think, this interpretation of the law will not last, but nevertheless, its not acceptable to confront antifascists with this kind of prosecution and its time that the jurisprudence is getting out of its ivory tower.
EDİT: for the issue of austrian NS prohibition and the freedom of speech see this