Peter Cooke is head of the employment department at Theodore Goddard.

Advocate General Michael Elmer delivered his opinion to the European Court of Justice (ECJ) in Grant v South West Trains on 30 September. He concluded that restricting family travel benefits for rail workers to partners in heterosexual relationships amounts to discrimination under article 119 of the Treaty of Rome.

Article 119 protects the right to equal pay for equal work, and is enforceable by individuals against their employer in many circumstances. Pay can include, for example, travel benefits and pensions. If the ECJ agrees with the Advocate General it will stretch article 119 to breaking point applying it to prohibit discrimination in pay, and probably treatment at work, on grounds of sexual orientation as well as on grounds of gender.

The Advocate General relies on P v S and Cornwall County Council (the transsexual case) to justify his opinion, but it is far easier to see that sacking a man on the grounds that he has become a woman is discrimination on grounds of sex than is depriving a partner of travel benefits.

Even in the first case, the usual requirement of comparison for the purpose of establishing discrimination has been de-emphasised the employer that dismisses a man who changes into a woman will presumably not treat a woman who changes into a man any differently.

Should the ECJ be making law in this area at all? The Court of Appeal in England refrained from doing so in R v MoD ex parte Smith, where the court decided the Treaty of Rome and the Equal Treatment Directive draftsmen were not addressing their minds in any way to problems of discrimination on grounds of sexual orientation.

Should the ECJ be seeking to create a new category of rights? The Treaty of Amsterdam will permit the European Commission to bring forward legislation on sexual orientation. It is difficult to see why the institutions of the EU find the problems arising from sexual orientation and gender reassignment more deserving of attention than, for example, race discrimination, on which there is no EU legislation.