(CNN) -- Sen. Larry Craig said he "overreacted and made a poor decision" in pleading guilty to disorderly conduct after his June arrest following an incident in a Minneapolis, Minnesota, airport bathroom.

A police mug shot of Sen. Larry Craig after he was arrested at the Minneapolis-St. Paul airport in June.

Tuesday, in his first public statement on the arrest, the Idaho Republican said he did nothing "inappropriate."

"Let me be clear: I am not gay and never have been," said Craig, who has aligned himself with conservative groups who oppose gay rights.

With his wife by his side, Craig said he is the victim of a "witch hunt" conducted by the Idaho Statesman newspaper.

"In pleading guilty, I overreacted in Minneapolis, because of the stress of the Idaho Statesman's investigation and the rumors it has fueled around Idaho," he said. "Again, that overreaction was a mistake, and I apologize for my misjudgment." Watch Craig say he did nothing wrong »

He added: "I should not have kept this arrest to myself, and should have told my family and friends about it. I wasn't eager to share this failure, but I should have done so anyway."

A police officer who arrested him June 11 said Craig peered through a crack in a restroom stall door for two minutes and made gestures suggesting to the officer he wanted to engage in "lewd conduct."

Craig's blue eyes were clearly visible through the crack in the door, Minneapolis-St. Paul International Airport police Sgt. Dave Karsnia wrote in the report he filed.

"Craig would look down at his hands, 'fidget' with his fingers, and then look through the crack into my stall again," Karsnia wrote in documents accompanying the arrest report.

Craig said the officer misinterpreted his actions.

After he was taken for questioning, the police report says, Craig pulled out a Senate business card and asked the officer: "What do you think of that?"

Before the senator spoke in Boise, Idaho, Tuesday, Senate Minority Leader Mitch McConnell, a Republican from Kentucky, informed Craig the leaders of his own party were calling for an ethics investigation into what they termed a "serious matter," a Senate Republican leadership aide told CNN.

The aide said senators, who discussed the matter by phone, were especially concerned about the business card allegation.

The GOP leadership consists of McConnell, Assistant Minority Leader Trent Lott of Mississippi, Conference Chairman Jon Kyl of Arizona, Policy Committee Chair Kay Bailey Hutchison of Texas, and Senatorial Committee Chair John Ensign of Nevada.

"Due to the reported and disputed circumstances, and the legal resolution of this serious case, we will recommend that Senator Craig's incident be reported to the Senate Ethics Committee for its review," the group said in a statement.

"In the meantime, Leadership is examining other aspects of the case to determine if additional action is required," the statement said.

Craig, 62, pleaded guilty August 8 to a misdemeanor disorderly conduct charge in the incident, according to Minnesota criminal records.

The senator said he "chose to plead guilty to a lesser charge in the hope of making it go away. I did not seek any counsel, either from an attorney, staff, friends, or family. That was a mistake, and I deeply regret it."

On Tuesday, Craig announced that he has retained an attorney.

The officer wrote he was on a plainclothes detail in the restroom because of citizen complaints and arrests for sexual activity there.

Karsnia wrote that when the person occupying the stall beside him left, Craig entered it and blocked the door with his rolling suitcase.

"My experience has shown that individuals engaging in lewd conduct use their bags to block the view from the front of their stall," the officer said in his report.

The senator then tapped his right foot, "a signal used by persons wishing to engage in lewd conduct," Karsnia wrote, and Craig ran his left hand several times underneath the partition dividing the stalls.

"The presence of others did not seem to deter Craig as he moved his right foot so that it touched the side of my left foot, which was within my stall area," the officer's report said.

When the police interviewed him later, the senator said that "he has a wide stance when going to the bathroom" and that was why his foot may have touched the officer's, the report said.

Craig also told police that he had reached down to the floor to pick up a piece of paper, the officer wrote.

"It should be noted that there was not a piece of paper on the bathroom floor, nor did Craig pick up a piece of paper," Karsnia wrote.

"During the interview, Craig either disagreed with me or 'didn't recall' the events as they happened."

After Craig ran his hand underneath the partition wall three times, Karsnia held his police identification down by the floor so the senator could see it, the report said.

"With my left hand near the floor, I pointed towards the exit. Craig responded, 'No!'

"I again pointed towards the exit. Craig exited the stall with his roller bags without flushing the toilet," Karsnia wrote.

The senator initially resisted the officer's request to go to the police operations center, he said, but finally did. There, he was read his Miranda rights, interviewed, photographed, fingerprinted and released, the report said.

The Capitol Hill newspaper Roll Call first reported the arrest Monday.

In a statement released Monday evening, Craig denied inappropriate conduct and said he regrets his guilty plea, which he entered without having an attorney present.

"At the time of this incident, I complained to the police that they were misconstruing my actions. I was not involved in any inappropriate conduct," he said. "I should have had the advice of counsel in resolving this matter. In hindsight, I should not have pled guilty. I was trying to handle this matter myself quickly and expeditiously."

Craig paid a $500 fine when he entered his guilty plea in Hennepin County Municipal Court in Bloomington, Minnesota, according to state criminal records.

In his petition to enter a guilty plea, Craig acknowledged that he "engaged in (physical) conduct which I knew or should have known tended to arouse alarm or resentment."

He also was required to stipulate in the statement that he would "make no claim that I am innocent of the charge to which I am entering a plea of guilty," the document said.

On Tuesday, Citizens for Responsibility and Ethics in Washington filed a complaint with the Senate Ethics Committee, asking that the senator's conduct be investigated. The group, which largely targets Republicans, asked the committee to probe whether Craig "violated the Senate Rules of Conduct by engaging in disorderly conduct," a statement said.

"If pleading guilty to charges stemming from an attempt to solicit an undercover officer in a public restroom is not conduct that reflects poorly upon the Senate, what is?" asked Melanie Sloan, the group's executive director, in a statement. Sloan is a former U.S. attorney in the Clinton administration's Justice Department.

Sen. Barbara Boxer, D-California, chairwoman of the Ethics Committee, declined to comment on whether an investigation would be conducted. Her office noted the committee's work is generally confidential.

A Senate aide familiar with Ethics Committee practices said ethics rules do not specifically require a member to disclose pleading guilty to a misdemeanor. But the rules require the panel to look into a matter and determine whether an investigation is appropriate once a formal complaint is lodged.

Craig resigned Monday night as a Senate liaison for former Massachusetts Gov. Mitt Romney's presidential campaign. Romney's son Josh canceled a trip to Idaho on Tuesday.

Craig, Idaho's senior senator, is married with three grown children and nine grandchildren. A former rancher, he was first elected to the Senate in 1990 after serving a decade in the House of Representatives. His seat is up for re-election in 2008.

Last fall, Craig's office publicly denied assertions by Internet blogger Mike Rogers that the senator is gay. Craig's office dismissed speculation about the senator's sexuality as "completely ridiculous."

In 1982, Craig denied rumors he was under investigation as part of a federal probe into allegations that lawmakers on Capitol Hill had sexual relationships with congressional pages, saying the "false allegations" made him "mad as hell."

He was never implicated in that investigation, which led to ethics charges against two other congressmen.

In recent years, Craig's voting record has earned him top ratings from social conservative groups such as the American Family Association, Concerned Women for America and the Family Research Council.

He has supported a federal constitutional amendment banning same-sex marriage, telling his colleagues that it was "important for us to stand up now and protect traditional marriage, which is under attack by a few unelected judges and litigious activists."

In 1996, Craig also voted in favor of the Defense of Marriage Act, which denies federal recognition to same-sex marriages and prevents states from being forced to recognize the marriages of gay and lesbian couples legally performed in other states.

Craig also has opposed expanding the federal hate crimes law to cover offenses motivated by anti-gay bias and, in 1996, voted against a bill that would have outlawed employment discrimination based on sexual orientation, which failed by a single vote in the Senate. E-mail to a friend

CNN's Dana Bash and Jessica Yellin contributed to this report.

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