Former Georgia congressman Bob Barr may run for president as a Libertarian, where his chief opponent would be one of two Democrats in this year's primaries who backs full marriage equality.

The man responsible for the most homophobic law ever passed by Congress is weighing a run for president as a Libertarian, despite that party's longtime claim to being strongly supportive of gay rights.

When Bob Barr was a Republican congressman from Georgia, he authored and was the chief sponsor of the Defense of Marriage Act, which blocks any federal recognition of gay couples married by the states, as well as allowing each state to refuse to recognizes marriage licenses issued to gay couples by other states.

Barr has always been a walking contradiction, defending the institution of marriage from gays even as he divorced his first two wives and is now on his third; he is also an ardent foe of abortion rights even though he supported a decision by his wife at the time to terminate a pregnancy. There are individual rights Barr does care about -- he's a longtime board member of the National Rifle Association.

Since leaving Congress in 2003, Barr has become active on privacy issues -- no, not the Roe v. Wade, Lawrence v. Texas kind. He's spoken out against the Patriot Act, joined the national board of the ACLU, and he did testify against a federal marriage amendment -- based on states' rights grounds.

Libertarians have a strong reputation on gay rights, including support gay marriage (or junking legal recognition for all relationships entirely) and repealing "Don't Ask Don't Tell." But they do oppose workplace protections (for any minority group) and hate crime laws (for any minority group.)

Barr would appear to be a very conservative peg in the Libertarian hole, but his candidacy could have a very significant benefit for gay rights -- siphoning off support for Republican John McCain, who remains unpopular with many conservatives.

Barr's chief opponent for the Libertarian presidential nomination may be former Alaska Sen. Mike Gravel, one of two Democratic presidential candidates who backed full marriage equality, who quit his party to join the Libertarian race. Gravel's gay marriage support is a better fir with the Libertarian platform, but his support for gay rights protections in the workplace and against hate crimes is not.