OLYMPIA, Wash. — A Republican state legislator who repeatedly voted against gay rights measures resigned his seat Wednesday amid revelations he reportedly had sex with a man he met at an adult video store while in Spokane, Wash., on a GOP retreat.

In a written statement, Richard Curtis, 48, who represents the 18th district in the state House of Representatives, said that while he believes he's done a lot of good during his time in the Legislature, "events that have recently come to light have hurt a lot of people."

"I sincerely apologize for any pain my actions may have caused," he said. "This has been damaging to my family, and I don't want to subject them to any additional pain that might result from carrying out this matter under the scrutiny that comes with holding public office."

On Monday, Curtis told The Columbian newspaper of Vancouver, Wash., that he did not solicit sex.

"I committed no crime," he said. "I did not solicit sex. I was trying to help somebody out."

Curtis, a former firefighter from La Center, Wash., also declared, "I am not gay."

In police reports, however, Curtis said the man he had sex with in a Spokane hotel room extorted him. The other man contends Curtis reneged on a promise to pay $1,000 for sex.

Curtis was among state GOP lawmakers in Spokane Oct. 24-26 for a retreat to discuss the upcoming legislative session. He went to the Hollywood Erotic Boutique early on Oct. 26 and met Cody Castagna, 26, of Medical Lake, Wash., who accompanied him to the hotel, according to police documents released Tuesday.

According to those documents, the two arrived at the hotel around 3:30 a.m. and had sex, after which Curtis fell asleep.

Curtis has alleged that Castagna took his wallet and later offered to return it for $1,000. Curtis said he only had $200 and left an envelope with the money at the hotel desk, according to the documents, which also said Castagna allegedly called Curtis and demanded an additional $800 and threatened to expose Curtis. But Curtis had already contacted police, who listened to the call and then met with Castagna.

There have been no arrests in the case. On Wednesday, Spokane County Deputy Prosecutor Larry Steinmetz said a decision about possible criminal charges in the alleged extortion case was weeks away.

Castagna appeared Tuesday at a Spokane news conference with his lawyer and said Curtis gave him his wallet to hold as collateral "for the money that he promised me." The lawyer refused to let his client tell reporters what he did for the money, noting Castagna had already spoken voluntarily with police.

"Cody Castagna admitted threatening to publicly expose Richard Curtis' gay lifestyle to his wife unless Richard Curtis provided the disputed money," the police documents said.

The lawyer also refused to let Castagna respond to a question about whether he threatened to "out" Curtis. The lawyer noted extortion "is a violent Class B felony" and declared that his client "didn't do anything wrong, at that level anyway."

Curtis' resignation was delivered to Washington Gov. Christine Gregoire Wednesday afternoon. A Republican successor will be chosen by county Republican leaders, and will serve until the 2008 election.

Curtis is married and has children, according to information on his legislative website, which was taken down after Curtis' resignation was accepted.

Elected to the Washington state House of Representatives in 2004, he voted in 2005 and 2006 against a bill that granted civil rights protections to gays and lesbians, and in 2007 voted against a bill that created domestic partnerships for same-sex couples. Both measures eventually passed the Democratic-controlled state Legislature and are now state law.

Efforts to reach Curtis or his lawyer by reporters have been unsuccessful.