Taken from wikipedia :
Laws against Holocaust denial
Holocaust denial is illegal in a number of European countries: Austria (article 3h Verbotsgesetz 1947), Belgium (Belgian Negationism Law), the Czech Republic under section 261, France (Loi Gayssot), Germany (§ 130 (3) of the penal code) also the Auschwitzlüge law section 185, Lithuania, The Netherlands under articles 137c and 137e, Poland, Romania, Slovakia, Spain and Switzerland (article 261bis of the Penal Code). In addition, under Law 5710-1950 it is also illegal in Israel.
The following punishments are used with regards to Holocaust Denial Laws: Austria (min: six months, max: twenty years (violent), ten years (non-violent)), Belgium (min: fine, max: one year), Czech Republic (min: six months, max: two years), France (min: fine/one month, max: two years), Germany (min: fine/six months max: five years), Israel (min: one year, max: five years), Lithuania (min: fine/two years, max: ten years (violent)), Poland (min: fine/three months, max: three years), Romania (min: six months, max: three years (public offender), five years (public servant offender)), Slovakia (min: fine/one month, max: three years) and Switzerland (min: fine/one year, max: fifteen months).
Many Holocaust deniers claim their work falls under a "universal right to free speech", and see these laws as a confirmation of their own beliefs, arguing that the truth does not need to be legally enforced. Some people who do not deny that the Holocaust occurred nevertheless oppose such restrictions of free speech, including, despite her legal battle with David Irving, Deborah Lipstadt. Another prominent opponent of the laws is Noam Chomsky. An uproar resulted when Serge Thion used one of Chomsky's essays without explicit permission as a foreword to a book of Holocaust denial essays. See: Criticism of Noam Chomsky. At times, Holocaust deniers seek to rely on Article 10 of the European Convention on Human Rights, which guarantees freedom of expression, when faced with criminal sanctions against their statements or publications. The European Court of Human Rights however consistently declares their complaints inadmissible. According to Article 17 of the Convention, nothing in the Convention may be construed so as to justify acts that are aimed at destroying any of the very rights and freedoms contained therein. Invoking free speech to propagate denial of crimes against humanity is, according to the Court's case-law, contrary to the spirit in which the Convention was adopted in the first place. Reliance on free speech in such cases would thus constitute an abuse of a fundamental right.