Gay marriage rose to the political forefront in 1996 when several gay couples from Hawaii sued for the right to legally marry. The anti-gay conservative response to the growing issue of gay marriage was The Federal Defense of Marriage Act (DOMA)
of 1996 which denies federal recognition of gay marriages and gives each state the right to refuse recognition of same-sex marriage licenses issued by other states. The act does not prohibit states from allowing gay marriages, neither does it obligate states to recognize the gay marriages from other states.
The Federal Defense of Marriage Act currently stands as law in the United States, but in the wake of the current gay marriage rights movement conservative groups are proposing the Federal Marriage Amendment
which would create a federal definition of marriage as "the union of a man and a woman," prohibiting states from issuing same-sex marriage licenses.
Due to the provisions of The Federal Defense of Marriage Act, marriage licenses granted to gay and lesbian couples in one state do not have to be recognized by another state. Therefore, gay marriage licenses issued in say Massachusetts are only valid in state of Massachusetts, unless other states chooses to recognize them. This forces married gay and lesbian couples to either reside in the states where their licenses were issued or lose the benefits of marriage in their home state. DOMA also denies gay and lesbian partners access to the federal benefits given to their partners.