During a press conference announcing that Missouri will allow married gay couples to file combined state tax returns, Governor Jay Nixon endorsed extending marriage rights to gay and lesbian couples in the state.

Nixon, a Democrat, announced Thursday that he had directed the Department of Revenue to accept the combined returns of gay couples married in a state where such unions are legal, 15 before the end of the year plus the District of Columbia.

“This is not about the definition of marriage, this is about the structure of our tax code and Missouri law, which is clear,” Nixon said, a reference to state law which requires couples who file a joint federal return to file a combined state tax return.

Following the Supreme Court's June decision striking down a portion of the Defense of Marriage Act (DOMA), the federal government announced it will recognize the marriages of gay couples for the purpose of benefits. The decision put pressure on so-called piggyback states without marriage equality to allow married gay couples to file jointly.

When asked his views on the subject, Nixon said he supported treating “folks” equally.

“Many Missourians, including myself, are thinking about these issues of equality in new ways and reflecting on what constitutes discrimination,” Nixon said. “For me, that process has led to the belief that we shouldn't treat folks differently because of who they are.”

“The question of whether same-sex marriage should be recognized in Missouri is a separate issue, one that I hope, quite frankly, Missourians have another chance to visit,” Nixon added.

Voters in 2004 approved an amendment to the Missouri Constitution defining marriage as a heterosexual union.