Conservative groups in the US have rallied around a House Bill introduced to protect groups opposed to equal marriage, religious and otherwise, from “discrimination by the government”.

Advocates of equal marriage have condemned the legislation as they say it legitimises homophobic discrimination, and protects those speaking out against gay people.

The Marriage and Religious Freedom Act, introduced last week was drafted by Representative Raul Labrador of Idaho.

Under the bill, no group could lose its tax-exempt status for speaking out against equal marriage. It would mean the federal government would also not be able to deny a grant, contract or employment to a person based on their belief that marriage should only be between one man and one woman.

In an interview last week he described it as a ”narrowly-tailored piece of legislation”, drafted out of a fear that the IRS and other federal agencies may unfairly target groups opposed to same-sex marriage, in the wake of the strike-down of the Defense of Marriage Act by the US Supreme Court in June.

Following the DOMA strike-down ”there were a lot of ideas about what to do,” Labrador said. “Some people looked at overturning it, or doing a constitutional amendment. I looked at the immediate need, which is the protection of religious institutions and churches, so that they can continue practising their religion as they see fit.”

When asked of any evidence of government discrimination against such groups, Labrador noted a California bill which would remove the tax-exempt status of the Boy Scouts of America (BSA), unless it fully accepted gay members, volunteers, and staff, and which was approved in the Senate in the US state of California back in May.

He also cited Democratic support of such a measure.

“This bill affirms that a person’s religious belief in the importance of natural marriage should be treated with tolerance and respect by the federal government,” said David Christensen, vice president for government affairs at the Family Research Council, which is promoting the bill.

The National Organization for Marriage, Focus on the Family, the Southern Baptist Convention’s Ethics & Religious Liberty Commission, Concerned Women for America and the US Conference of Catholic Bishops are all in support of the bill.

Gay rights groups have voiced anger at the introduction of the bill, saying there is no need to provide more protections for such groups, when the First Amendment is already in place to provide such.

“It automatically goes after a specific community of people and gives free license to say, ‘It’s OK to discriminate against this group,’” said Ross Murray, director of news and faith initiatives at GLAAD, a leading gay rights organization.

“I have a real hard time as a Christian fathoming why someone as a Christian would want to actively hurt another person, wanting to block them from receiving goods and services, want to block them from purchasing goods and services like everyone else does,” Murray continued.

“There is no evidence that federal programs have or would discriminate against people because of their religious beliefs about marriage,” said Fred Sainz, a spokesman for the Human Rights Campaign.

“What is clear, however, is that this legislation would give a free pass to federal workers, recipients of taxpayer-funded grants and others to discriminate against lawfully married couples.”

“This bill will set a very dangerous precedent,” Sainz said in an email to the Washington Post. “Accommodating religious beliefs on marriage may only be the beginning. The bill’s language makes clear that it should be interpreted as broadly as possible. Should federal workers and those who do business with the government get to turn away anybody they do not like based on religion — unmarried pregnant women? Atheists?  Muslims?  Or even another member of their own faith with different views?”

The Marriage and Religous Freedom Act is co-sponsored by 58 Republicans and 2 Democrats.