composition of the prison population. As Lord Mance has pointed out, only 8 per cent of persons convicted of an offence in England and 15 per cent in Scotland are sentenced to imprisonment. A statistical breakdown of the prison population as at 30 September 2010 suggests that 85% of prisoners serving sentences of less than five years were convicted of violent or sexual offences, robbery, burglary, theft, handling, fraud, forgery or drug offences. No doubt the threshold of seriousness for the passing of a sentence of imprisonment will vary in practice from one country to another. Different offences will perfectly properly be regarded as having more serious implications for some societies than for others. The United Kingdom is widely thought to have a relatively low threshold, but I am not aware that any comprehensive comparative study has been carried out which takes account of the underlying patterns of criminality. 130. Although article 3 of the First Protocol is in unqualified terms, the jurisprudence of the Strasbourg Court has acknowledged from the outset that the right to vote may be subject to limitations of a kind which is familiar in the caselaw governing other Convention rights. The limitations must pursue a legitimate aim by proportionate means and must not be such as to impair the essence of the right: see Mathieu-Mohin and Clerfayt v Belgium (1988) 10 EHRR 1, para 52; Matthews v United Kingdom (1999) 28 EHRR 361, para 63. It has generally been held that the essence of the right is not impaired if it does not thwart the free expression of the opinion of the people as a whole: see Holland v Ireland (Application No 24827/94) (unreported) 14 April 1998. It follows that the exclusion of certain categories of person from the franchise may be compatible with the Convention notwithstanding that as far as those persons are concerned the exclusion is total while it lasts. The case-law has consistently emphasised that these are matters on which the state enjoys a wide margin of appreciation. In Hirst this was said to reflect the “numerous ways of organising and running electoral systems and a wealth of differences, inter alia, in historical development, cultural diversity and political thought within Europe which it is for each Contracting State to mould into its own democratic vision” (para 61). 131. The United Kingdom government argued before the Strasbourg Court in Hirst that the objective of disenfranchisement was to serve as an additional punishment. The court accepted that that was a possible rationalisation, and regarded it as a legitimate objective, compatible with article 3 of the First Protocol. The rule was nevertheless held to be incompatible because it was disproportionate, “essentially as it was an automatic blanket ban imposed on all convicted prisoners which was arbitrary in its effects and could no longer be said to serve the aim of punishing the applicant once his Page 60