As predicted, voters in North Carolina approved a state constitutional ban on same-sex marriage that, due to its vague language, will also make other domestic arrangements such as civil unions and domestic partnerships illegal — for both gay and straight couples.

Additionally, the ACLU of North Carolina has raised concerns [PDF] that Amendment One could invalidate certain domestic violence laws that protect unmarried people, as well as child custody rights and other private agreements, including wills and powers of attorney.

The President, through his North Carolina spokesman Cameron French, expressed disappointment at the ban's approval.

"He believes the North Carolina measure singles out and discriminates against committed gay and lesbian couples, which is why he did not support it," said French. "President Obama has long believed that gay and lesbian couples deserve the same rights and legal protections as straight couples and is disappointed in the passage of this amendment."

Obama has come under heavy fire in recent days for refusing to take a definitive stand for or against same-sex marriage, opting instead to equivocate by saying his position was "evolving"

Opponents of the ban have said they plan to "look at all legal options and political options to overturn this amendment." Unlike a state law, which is relatively easy to reverse, overturning a constitutional amendment "requires a three-fifths vote in both legislative houses, then voter approval," according to the Associated Press.

With the passage of Amendment One, North Carolina became the 31st state to adopt a constitutional same-sex marriage ban. The Guardian yesterday published a helpful interactive infographic which breaks down gay rights in the US state by state.

[photo via AP]