Former congressman from Massachusetts Barney Frank (D), shown in 2014, testified before the House Oversight Committee Tuesday. (Win McNamee/Getty Images)

With a Supreme Court ruling last year, Republicans and social conservatives lost their battle against same-sex marriage. But that doesn’t mean they are stopping their fight.

Like their use of restrictive legislation to undermine the long-established right to abortion, they are looking for ways to weaken the reach of the court’s decision. Maybe there’s something to be said for tenacity. But that’s taking them, again, to the wrong side of history.

The current vehicle for opposition to the law of the land is the First Amendment Defense Act — a nobler title is hard to find.

Sen. Mike Lee (R-Utah), sponsor of the legislation, told a House hearing Tuesday, “The bill reaffirms the letter and spirit of the First Amendment, by stating unequivocally that the federal government may not revoke or deny a federal tax exemption, grant, contract, accreditation, license or certification to an individual or institution based on a religious belief about marriage.”

But at question is offensive action, not a belief. Just as opposition to same-sex marriage is protected by the bill, so is the belief “that sexual relations are properly reserved” to marriage between one man and one woman.

The effect of the legislation, cloaked in the rhetoric of freedom of speech and religion, could be widespread, according to more than 3,000 religious leaders who signed a letter against the bill and the Democrats who oppose it.

Katherine Franke, a Columbia Law School professor, provided a list of actions that federal officials would not be permitted to stop if the legislation becomes law. Among other things, the measure would prevent federal authorities from “enforcing the Fair Housing Act against a landlord that advertises that it will not rent to unmarried parents,” Franke said. Federal government officials also would not be able to move against health-care providers who “denied coverage for mandated preventative services — such as counseling for sexually transmitted infections, contraception, or domestic violence screening and counseling — to employees who are married to a same-sex partner or who have extramarital relations or sex.”

It’s a pretty good bet that supporters of the bill are not married to a person of the same sex, but how many of them have had no sex outside marriage? I’d like to see them answer that under oath.