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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