The case-law of the Court is taking in consideration the frame of the domestic legal system concerned: therefore, on the one side, it is very strict in reviewing compliance with the principle of equality and, on the other side, it allows the States in the matter a great margin of appreciation to balance the requirement of the protection of the minorities with the national, traditional constitutional and electoral arrangements. The Court declared, in the Mathieu-Mohin & Clerfayt v. Belgium judgment,² that “[t]he rights [enshrined in Article 3 of the Additional Protocol to the Convention] are not absolute.. the Court… has to satisfy itself that the conditions do not curtail the rights in question to such an extent as to impair their very essence and deprive them of their effectiveness; that they are imposed in pursuit of a legitimate aim; and that the means employed are not disproportionate… In particular, such conditions must not thwart ’the free expression of the opinion of the people in the choice of the legislature’…It does not follow, however, that all votes must necessarily have equal weight as regards the outcome of the election” (so-called "amplifier effects"). This conclusion leaves space for a policy of reverse discrimination if a legitimate aim is pursued and the free choice of the electors is not thwarted.