The Washington Post is reporting that President Bush will announce today his endorsement of a constitutional amendment that would define marriage as the union of a man and a woman and that would bar same sex marriages. According to White House advisors, the amendment would not prevent state legislatures from allowing for civil unions and same-sex partnership arrangements but critics disagreed. But the head of Freedom to Marry said the proposed amendment is written in a manner that “is intended to deny any other measure of protection, including civil unions and domestic partnerships.”