Case Sporrong and Lὂnroth v Sweden 7151/75 [1982] ECHR 5
III. That the absence of a reasonable relationship of proportionality between the means employed and the aim sought to be realised is not established and certainly is not clearly established; that with regard to the reply given to the second limb of the fifth question, the judgment has not sufficiently taken account of the rule according to which the national authorities, who are in the first place those who must appreciate the requirements implied by the factual and legal features in issue, remain free to choose the measures which they consider appropriate in those matters which are governed by the Convention.
51. As previously stated, the confiscation order constituted a “penalty” within the meaning of the Convention. It therefore falls within the scope of the second paragraph of Article 1 of Protocol No. 1, which, inter alia, allows the Contracting States to control the use of property to secure the payment of penalties. However, this provision must be construed in the light of the general principle set out in the first sentence of the first paragraph and there must, therefore, exist a reasonable relationship of proportionality between the means employed and the aim sought to be realised (see, among many examples, Allan Jacobsson v. Sweden (no. 1), judgment of 25 October 1989, Series A no. 163, p. 17, § 55).