The Arizona Republic, Cheryl Evans, File) MARICOPA COUNTY OUT; MAGS OUT; NO SALES, Associated Press
FILE - In this July 31, 2010 photo, Republican state Sen. Scott Bundgaard speaks at a candidates forum in Buckeye, Ariz. Bundgaard is expected to testify Friday as the Senate Ethics Committee resumes a hearing that could result in a recommendations from a reprimand to explusion from the Legislature for a domestic violence incident.

PHOENIX — Sen. Scott Bundgaard resigned from the Arizona Legislature on Friday, stepping down shortly before he would have testified before the Senate Ethics Committee on whether he should be disciplined for a February domestic incident involving a former girlfriend.

The resignation ends an ethics case that could have resulted in committee members recommending that the full Senate issue a letter of reprimand, formally censure Bundgaard or expel him.

Bundgaard's ex-girlfriend, Aubry Ballard, testified Thursday that he struck her twice and threw her cellphone out the window while they drove and then stopped on a Phoenix freeway and pulled her out of his car.

Ballard said she reacted to being hit in the chest by slapping Bundgaard in the face. Both had cuts and bruises after the Feb. 25 confrontation, she said.

Ballard testified that the confrontation followed an argument over his decision to take dancing lessons while failing to take the time to get counseling for a previous physical altercation.

The incident prompted fellow Senate Republicans to replace Bundgaard as Senate majority leader in March.

Bundgaard, a Peoria Republican, wrote Friday in his brief letter to the Senate president that he was resigning "with deep regret." He didn't specifically mention the ethics proceeding or the confrontation with Ballard.

Senate Majority Leader Andy Biggs, a retired attorney and an Ethics Committee member, said evidence presented during the hearing was "pretty damaging." Bundgaard clearly wanted to tell his side of the story but he seemed to have concluded he couldn't recover politically, Biggs said.

Bundgaard has denied assaulting Ballard. He pleaded no contest Aug. 16 to a misdemeanor endangerment charge under a plea agreement. It included dismissal of an assault charge and a requirement that he get domestic violence counseling.

Bundgaard attorney Andre Merrett told the committee on Thursday that his client regretted his role in the altercation but shouldn't be punished by the Senate because he never intended to harm Ballard or put her at risk.

But the lawyers serving as the committee's independent counsels said expulsion would be warranted because Bundgaard assaulted Ballard and lied to police and others about his actions and claimed legislative immunity that prevented police from arresting him that night.

"In this case, you not only have domestic violence, you've got obstruction of justice," attorney Cory Langhofer said Friday, following Bundgaard's resignation. "Expulsion would have been the only appropriate remedy."

The Maricopa County Board of Supervisors will appoint a replacement to fill the Senate vacancy. The replacement must be a Republican.

Bundgaard was elected to the state House of Representatives in 1994 and the state Senate in 1996, serving there for six years before staging an unsuccessful run for the U.S. House in 2002.

Following the congressional campaign, then-President George W. Bush appointed him to the White House Commission for Presidential Scholars and the Presidential Scholars Foundation Board. Bundgaard returned to the Senate in 2011.

Bundgaard didn't immediately respond to phone and email messages seeking comment on Friday. He was to have testified in the afternoon, but the hearing was halted after a lunch break when Merrett told the committee that further proceedings weren't necessary.

Another Bundgaard attorney, Shawn Aiken, later said his client decided during the break to resign. Aiken said he believed the hearings were going well considering the defense hadn't yet put on its case.

Ballard said she hoped Bundgaard's resignation would allow her to put the "unfortunate assault in the past and to get on" with her life. A statement she issued through a publicist thanked law enforcement officials and the committee.

Bundgaard's resignation was the best move for him, his family and the Senate, said Senate President-designate Steve Pierce. It eliminated what would have been a distraction at the beginning of the Legislature's 2012 session, he said.

The resignation also shows that the Senate holds its members to account, said Sen. Steve Gallardo, a Phoenix Democrat.

"No one is above the law," he added.

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