It seems that judges can only declare things unconstitutional when liberals approve. In Spain, "liberal" lawmakers are pushing to have judges who are challenging the constitutionality of a Spanish law authorizing homosexual "marriages" punished.[1] Apparently having an independent judiciary is either unknown there, or less important than being all "progressive."
The argument being made is interesting. Apparently only where the right to marry is defined in the constitution are the two sexes independently specified. The Judge is saying that this, along with the fact that "heterosexuality is the substantial and identifying element of the institution of marriage," creates a Constitutional requirement that the couple be heterosexual. I hope he prevails.
[1] Catholic News Agency. "Another Spanish judge questions constitutionality of gay 'marriage'" Catholic News Agency (online) 2005-09-07. http://www.catholicnewsagency.com/new.php?n=4822