Holocaust denier jailed for three years

[Pharaoh]

I know he was found guilty and that he even pleaded guilty. So, yes, he was guilty of Holocaust denial, but I'm puzzled as to what exactly Holocaust denial entails, because I haven't read that he denies large numbers of Jews were killed by the Nazis, he just argues over the details. It seems a historian doesn't even have to completely deny Nazis killed Jews to be found guilty and jailed.