Conservative group The Heritage Foundation on Friday announced its opposition to the Employment Non-Discrimination Act (ENDA).

ENDA seeks to ban workplace discrimination based on sexual orientation and gender identity. The bill cleared a Senate committee with the help of three Republicans in July and is expected to reach the full Senate on Monday.

Heritage and its president, former South Carolina Senator Jim DeMint, are credited with playing a prominent role in the Republican Party's shift to the right and increasing demands that President Barack Obama repeal or defund the Affordable Care Act, also known as ObamaCare.

“ENDA is bad public policy,” Heritage Action for America, the group's political arm, wrote on Friday.

“The legislation would severely undermine civil liberties, increase government interference in the labor market, and trample on religious liberty. It is flawed public policy based in part on the tenuously defined term 'gender identity,' which is commonly understood to be subjective, self-disclosed, and self-defined.”

In rejecting the bill, the group cited a National Review op-ed written Ryan T. Anderson, the William E. Simon fellow in Religion and a Free Society at The Heritage Foundation and a vocal opponent of gay marriage.

“Some defenders of the bill reply by saying that sexual orientation and gender identity are just like race, and thus deserve similar federal protections,” Anderson wrote. “But this analogy is false. Jim Crow laws represent pervasive, onerous, and legally enshrined obstacles to employment based on race.”

“What's more, while race is usually readily apparent, the groups seeking special status in ENDA aren't defined by objective characteristics. Sexual orientation and gender identity are commonly understood to be subjective, self-disclosed, and self-defined. And unlike race, sexual orientation and gender identity are usually understood to include behaviors.”

Heritage Action concluded with a warning to Republican Senators: “Heritage Action opposes ENDA and will include it as a vote on our legislative scorecard.”