“14. … Discrimination means a failure to treat like cases alike. There is obviously no discrimination when the cases are relevantly different…. There is discrimination only if the cases are not sufficiently different to justify the difference in treatment….” 15. Whether cases are sufficiently different to justify the difference in treatment is partly a matter of values and partly a question of rationality. Article 14 expresses the Enlightenment value that that every human being is entitled to equal respect and to be treated as an end and not a means. Characteristics such as race, caste, noble birth, membership of a political party and … gender, are seldom, if ever, acceptable grounds for differences in treatment … the Strasbourg court has given [article 14] a wide interpretation… and it is therefore necessary … to distinguish between those grounds of discrimination which prima facie offend our notions of respect due to the individual and those which merely require some form of rational justification…. 16. There are two important consequences of making this distinction. First, discrimination in the first category cannot be justified merely on utilitarian grounds, e.g. that it is rational to prefer to employ men rather than women because more women give up their employment to look after children. That offends the notion that everyone is entitled to be treated as an individual and not a statistical unit. On the other hand, differences in treatment in the second category (e.g. on grounds of ability, education, wealth, occupation) usually depend upon considerations of the general public interest. Secondly, while the courts, as guardians of the right of the individual to equal respect, will carefully examine the reasons offered for any discrimination in the first category, decisions about the general public interest which underpin differences in treatment in the second category are very much a matter for the democratically elected branches of government. 17. There may be borderline cases in which in which it is not easy to allocate the ground of discrimination to one category or the other and … there are shifts in the values of society on these matters … But there is usually no difficulty about deciding whether one is dealing with a case in which the right to respect for the individuality of a human being is at stake or merely a question of general social policy …”
“51. Article 14 does not prohibit a Member State from treating groups differently in order to correct “factual inequalities” between them; indeed in certain circumstances a failure to attempt to correct inequality through different treatment may in itself give rise to a beach of the article … A difference in treatment is, however, discriminatory, if it has no objective and reasonable justification; in other words, if it does not pursue a legitimate aim or if there is not a reasonable relationship of proportionality between the means employed and the aims sought to be realised. The Contracting State enjoys a margin of appreciation in assessing whether and to what extent differences in otherwise similar situations justify a different treatment. 52. The scope of this margin will vary according to the circumstances, the subject matter and the background … As a general rule, very weighty reasons would have to be put forward before the Court could regard a difference in treatment based exclusively on the ground of sex as compatible with the Convention … On the other hand, a wide margin is usually allowed to the State under the Convention when it comes to general measures of economic or social strategy …”
“ … [M]arriage remains an institution which is widely accepted as conferring a particular status on those who enter it. The situation of the applicant is therefore not comparable to that of a widow”…. In any event… a difference in treatment is discriminatory for the purposes of Article 14 if it “has no objective and reasonable justification”, that is if it does not pursue a “legitimate aim” or if there is not a “reasonable relationship between the means employed and the aim sought to be realised …. Further, the Court reiterates that “States enjoy a certain margin of appreciation in assessing whether and to what extent differences in otherwise similar situations justify a different treatment in law…”
“We have considered the position of unmarried couples. The Government recognises and supports marriage. The contributory system had always been based on legal marriage. Marriage provides a straightforward method of deciding whether benefits should be paid. We believe that there would be difficulties in defining and establishing entitlement for unmarried couples at what would be a most difficult and sensitive time. Intrusive questioning would be hard to avoid.”