"There is room for implied limitations and Contracting States must be given a wide margin of appreciation in this sphere (Mathieu-Mohin and Clerfayt v. Belgium, judgment of 2 March 1987, Series A no. 113, p. 23 § 52). The State’s margin of appreciation, however, is not unlimited. It is for the Court to determine in the last resort whether the requirements of Protocol No. 1 have been complied with. It has to satisfy itself that any such 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” (see Gitonas and Others v. Greece, judgment of 1 July 1997, Reports of Judgments and Decisions 1997-IV, p. 233, § 39; Matthews v. the United Kingdom [GC], no. 24833/94, § 63, ECHR 1999-I; Podkolzina v. Latvia, no. 46726/99, § 33, ECHR 2002-II; and Mathieu-Mohin and Clerfayt, cited above, p. 23, § 52). "