As I understand it (which could be wrong, I have no particular knowledge on this topic), he ran as a member of a different party that has not faced the same legal classifications. He used to be a councillor for NPD, which is the one a court described as Nazi-like and unconstitutional. In this election he ran for Free Saxons, who do appears to be far-right loons in their own way but who don’t seem to be so clearly Nazi-ish. NYT is right to point out his connection to NPD, though