The U.S. Supreme Court has scheduled an April 28 hearing on whether Washington state officials can release the names of signers of a ballot measure that sought to repeal a gay rights law.

The court agreed to hear the case in January after Protect Marriage Washington appealed a 9th Circuit Court of Appeals decision that ordered the release of nearly 138,000 signatures that put Referendum 71 on last fall's ballot.

Referendum 71 asked voters to accept – or reject – a domestic partnership law approved by lawmakers that gives gay couples all the rights of marriage. Voters opted to keep the law.

Opponents say releasing the names would put signers at risk of harassment, reprisals and boycotts of their businesses, amounting to an unconstitutional infringement of free speech rights.

Gay rights groups announced early in the campaign their intention to make the names public via the Internet.

Under Washington state law, names of people who sign petitions become public record after the Secretary of State verifies a petition, but Referendum 71 names have remained sealed pending the court's decision. State officials argue that the names should be released because signers are acting in place of lawmakers, who do not approve laws in secret.

The case – Doe No. 1 v. Reed – is the first of two cases headed to the Supreme Court that stem from gay rights actions. The high court has also agreed to hear a case that concerns shielding the identities of defendants in January's first federal case to challenge the constitutionality of a gay marriage ban. In that case, gay rights opponents have also said that they fear reprisals if their views are made public.

While rulings in neither case will affect gay rights legislation directly – the cases deal with questions of privacy – they will be an early signal of how the court could rule on several gay rights cases wending their way through the federal system.

All the cases involve the right of gay and lesbian couples to marry and are expected to reach the Supreme Court within the next couple of years. The state of Massachusetts has sued the federal government because the Defense of Marriage Act (DOMA) blocks married gay couples from accessing federal benefits. A case that originated in California asks the Supreme Court to invalidate Proposition 8, the state's gay marriage ban. And a third lawsuit, filed by Boston-based gay rights group GLAD, also challenges portions of DOMA, but would have limited effect beyond Massachusetts.