Civil unions should not be reserved for heterosexual couples, the European Court of Human Rights (ECHR) ruled Thursday, condemning Greece for creating a "life partner" legal category that excludes gays.
Judges in Strasbourg said that authorities in Orthodox Christian Greece had not offered "convincing and weighty reasons capable of justifying the exclusion of same-sex couples" when passing a 2008 law.
Grigoris Vallianatos and Nikolaos Mylonas, two Greek gay men, alleged with three other couples that the law infringed their right to respect for their private and family life, a clause in the European Convention on Human Rights, and amounted to unjustified discrimination.
The court noted that European states have no obligation to provide some form of legal recognition for gay relationships.
But of the 19 states which authorise some form of registered partnership other than marriage, Lithuania and Greece "are the only ones to reserve it exclusively for couples of the opposite sex," the Court said.
Fewer than than half of the 47 signatories to the European Convention on Human Rights, of which the Court is the judicial enforcer, have introduced such alternatives to marriage.
The Court said that as the two men had found themselves in a "similar situation" to heterosexual couples offered the protection of civil partnerships, they too deserved legal protection.
"Although European countries' legislation on the issue was not entirely uniform," the Court conceded, "there was nevertheless a trend towards legal recognition of same-sex couples."
Furthermore, "Greece was the only country to have enacted legislation governing a form of civil partnership while under the same legislation excluding same-sex couples from its scope," it said.
The law passed in November 2008 generated significant debate in Greece, whose Orthodox Church remains a powerful conservative force.
Greece will now be compelled to change the law.