And it has singled out, in particular, Spain, a Catholic country that has legalized gay marriage, as the worst offender.

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Indeed the absence of long-lasting controversy over the issue in Spain and Portugal is often adduced as an argument by supporters of gay marriage in France.

BBC: France's gay marriage fight

This is the case in other "Catholic" countries like Spain and Portugal, which have recently adopted gay marriage.

BBC: France's gay marriage fight