Rep. Michele Bachmann (R-MN) became the first presidential candidate to sign a pledge created by The Family Leader, a conservative, Iowa-based Christian group that opposes same sex marriage, Sharia law and pornography.

By signing the pledge (PDF), Bachmann vowed to support a constitutional amendment banning same sex marriage, as well as agreeing that same sex marriage was akin to polygamy.

The document also implies that homosexuality is a choice.

"No peer-reviewed empirical science or rational demonstration has ever definitively proven, nor has even shown an overwhelming probability that homosexual preference or behavior is irresistible as a function of genetic determination or other forms of fatalism," according to the Christian group.

With her signature, Bachmann seemed to be implicitly agreeing that black children were better off during slavery.

"Slavery had a disastrous impact on African-American families, yet sadly a child born into slavery in 1860 was more likely to be raised by his mother and father in a two-parent household than was an African-American baby born after the election of the USA’s first African-American President," the document said.

"Given that families were broken up regularly for sales during slavery and that rape by masters was pretty common, this could not be more offensive," Jack & Jill Politics' Cheryl Contee noted.

As a part of the pledge, Bachmann promised to ban "all forms of pornography and prostitution, infanticide, abortion and other types of coercion or stolen innocence."

The Minnesota Republican also agreed that Sharia law is a "form of totalitarian control."

"If you are looking at being a leader of our great country... we would like to have you pledge personal fidelity to your own spouse and a respect for the marital bonds of others," The Family Leader CEO Bob Vander Plaats said Thursday.

Bachmann aide Alice Stewart told The Des Moines Register that the candidate quickly signed the pledge because "[s]he has been married for over 30 years and has a strong marriage and faith."