Forty Senate Democrats have signed on to a letter calling for the rejection of an amendment that would allow adoption agencies to refuse gay and lesbian couples.

The amendment, introduced by Representative Robert Aderholt, a Republican from Alabama, would prohibit federal, state and local governments from denying funds to adoption agencies that have “declined or will decline to provide, facilitate or refer for a child welfare service that conflicts with … the provider's sincerely held religious beliefs of convictions.”

State and local governments that violate the law would be penalized with a fifteen percent cut in federal funding.

The amendment is attached to funding legislation for the Departments of Labor, Health & Human Services and Education. It cleared a House panel earlier this month.

Oregon Senator Ron Wyden is leading the effort against the measure.

“Allowing child welfare agencies to close the door to willing and fully qualified foster and adoptive parents due to a difference in religious belief opens the door to taxpayer-funded discrimination and deprives vulnerable children of safe and loving homes,” the senators wrote. “We strongly encourage you to reject this language and instead, support federal laws and regulations barring discrimination, and protect the rights of all qualified parents who answer the call to foster and adopt children in foster care.”

In a statement, the American Civil Liberties Union (ACLU), called the amendment “unacceptable.”

“There are over 118,000 children awaiting adoption in the United States,” said the ACLU's Ian Thompson. “The best way to provide loving and stable homes for these children is to have as many qualified prospective foster and adoptive parents as possible. Today, 40 members of the Senate – led by Senator Wyden (D-OR) – joined leading child welfare organizations and civil rights advocates in saying that discrimination has no place in our child welfare system because every child deserves the opportunity to grow up with the support of a loving family. We join these senators in making clear that the discrimination and harm that would be caused by the Aderholt Amendment is unacceptable.”

Nine states – Alabama, Michigan, Mississippi, North Dakota, South Dakota, Texas, Virginia, Oklahoma and Kansas – have enacted similar laws.