TRENTON, N.J. — A New Jersey church group is suing the state over whether the organization should be required to allow a lesbian couple to hold a civil-union ceremony at a beachfront pavilion owned by the group.

The Ocean Grove Camp Meeting Association, a Methodist group, says its rights are being violated by a state investigation into its decision to reject the couple's application.

The group also says that by finding enough reason to investigate the complaint, the state's Division on Civil Rights is threatening to prosecute the group in order to force it to allow such ceremonies to take place.

The group said it rejected the application because the church does not recognize same-sex unions.

"Religious groups have the right to make their own decisions without government interference. The government can't force a private Christian organization to use its property in a way that would violate its own religious beliefs," said Brian Raum, a lawyer for the Alliance Defense Fund, which is representing the Ocean Grove church group.

The couple, Harriet Bernstein and Luisa Paster of Ocean Grove, applied in March to rent the pavilion for a Sept. 30 ceremony.

After their application was rejected and their $75 deposit returned, the couple said they contacted the association's president, who told them the facility could not be used for civil-union ceremonies.

The couple filed a complaint with the New Jersey Division on Civil Rights, saying the rejection was a violation of the state's law against discrimination. They asked the division to require the association to allow the ceremony to take place.

In the lawsuit filed yesterday, the organization said if it were to allow civil-union ceremonies for same-sex couples to take place, it would constitute approval of such unions. The lawsuit also says the state's investigation has forced the association to limit use of the pavilion for weddings out of fear of prosecution.

The association wants to make sure it will not be forced by the state to allow its buildings and facilities to be used in a way that violates its members' religious beliefs.

In a statement, Lee Moore, a spokesman for the state's attorney general, described the lawsuit as "premature," saying the division hasn't come to any conclusion about the case.

"To date, the Division on Civil Rights has asserted nothing beyond its right to initiate an investigation to determine whether there has been a violation of the law against discrimination," Moore said.

Moore said it was the first investigation to deal with the issue of where a civil-union ceremony could be performed since the civil-union legislation became law. He said the state had previously received two complaints having to do with receiving job benefits.

Bernstein, one of the women who wanted to use the pavilion, said she and her partner had been in discussions, mediated by the division, with the association to resolve the matter. She said it appeared as if a settlement was within reach until yesterday's lawsuit was announced.

Bernstein said that in the past, the pavilion had been used for civil-wedding ceremonies as well as for people of all faiths to get married. She said it also had been used for concerts and impromptu gatherings.

"In an apparent distortion of the First Amendment, they are claiming that they have the right to discriminate against people who do not share their religious tenets," she said.

The association says it uses the pavilion for a variety of programs such as a Sunday morning worship service and a Bible school class, and has rented the pavilion for wedding ceremonies. When the pavilion is not in use, members of the public are allowed to sit and rest in it to escape the sun or rain.

However, the association said members of the public using the pavilion are always required to follow the association's rules.

Steven Goldstein, the head of Garden State Equality, called the lawsuit "preposterous."

"For decades, the boardwalk and other areas in Ocean Grove have been used by the public," Goldstein said.