BERLIN (AP) -- Gay rights campaigners won a victory over the German government Thursday as the country's top court ruled that homosexual couples in civil unions should receive the same tax benefits as heterosexual married couples.
The Federal Constitutional Court in Karlsruhe ruled that treating the two forms of partnership differently for tax purposes violates the country's guarantee of equal rights.
Chancellor Angela Merkel's center-right government had long resisted granting the same tax benefits to gay couples in civil unions. Those unions — officially certified by a notary and carrying similar rights and duties to wedlock — are widely accepted by Germany's gay community as equivalent to marriage.
The court said that treating civil unions differently amounts to "unequal treatment because of sexual orientation." Failure to be vigilant in guaranteeing equality "leads to discrimination against a minority," it warned.
Married couples in Germany are able to jointly declare their taxable incomes, which can significantly lower their overall tax burden especially when one partner has higher pay. The rule costs the government annually about 15.5 billion euros ($20 billion), although it estimates that extending the same right to the country's some 27,000 civil unions will only add about 30 million euros to the bill.
The court acknowledged that married couples enjoy special privileges because the partners also accept a strong responsibility for each other, including financial, but it argued that the civil union implies the same duties and responsibilities for gay partners.
The court ordered the government to retroactively amend the relevant laws dating back to 2001, when civil union status was first introduced by a previous center-left government.
Two of the court's eight judges issued a dissenting minority opinion, but that does not affect the validity of the verdict.
The government vowed it will seek to get the necessary legislation passed by this fall to implement the court decision.
Gay rights campaigners cheered the court decision.
"This is a full-blown victory," said opposition lawmaker Volker Beck, an outspoken gay-rights advocate. He added that the next hurdle should be to grant gay couples equal rights when it comes to adoption.
"The principle of equal treatment is valid for all citizens, independently of their sexual orientation," said the German Association of Lesbians and Gays. Merkel's government "refuses to learn that lesson by all means."
Granting more rights to homosexual couples is relatively uncontroversial among the wider public in Germany — unlike in France where repeated protests against legalizing gay marriage this year have seen tens of thousands take to the streets.
Still, conservative politicians from Merkel's Christian Democratic Union party — historically close to the Christian churches — have argued that married couples must enjoy higher protection and tax benefits because they usually have children. But the court struck down that argument, saying that policies in favor of families and children cannot be promoted by discriminating against civil unions.
The decision now comes as a blow to Merkel only three months ahead of federal elections. Her governing coalition resisted calls to grant civil unions the same rights as married couples, despite an earlier ruling by the country's top court which strongly indicated that the judges in Karlsruhe were almost certain to rule against the government in this case.
Several opposition leaders say Merkel's government has failed to show leadership on the issue, and instead let the court take the lead to avoid a possible backlash from her conservative voter base.
"Merkel's coalition is driven by the Federal Constitutional Court," said lawmaker Thomas Oppermann of Germany's main opposition party, the Social Democrats. "She still does not want to realize that the time has long come for fully equal treatment of civil unions and marriage," he added.
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