A Utah Highway Patrol trooper has resigned and pleaded guilty to two misdemeanor charges stemming from a relationship with a teenage girl.

Nick Sivulich, 44, pleaded guilty Tuesday in 2nd Circuit Court to charges of contributing to the delinquency of a minor and lewdness, both class B misdemeanors. Charges were filed earlier in the day. Sivulich, of Roy, resigned from the highway patrol about two weeks ago, attorneys said.The crimes are punishable by jail terms of up to six months and a fine of up to $1,000. Sentencing is set for Oct. 22.

Defense lawyer John Caine said that while Sivulich was a trooper at the time he was involved with the girl, the contact was off-duty. "It did not have anything to do with the UHP," agreed Weber County Attorney Reed Richards.

The incidents occurred over the past two years, while the girl was 14 and 15 years old. She is now nearly 16.

Richards said the girl claimed Sivulich had an affair with her. Sivulich's version is that he associated with her, Richards said. Sivulich denies any sexual involvement with the girl.

Caine said the girl was infatuated with Sivulich and made serious allegations against him.

The relationship was "consentual" and was "initiated by her," Sivulich's lawyer said. Caine also said Sivulich never admitted breaking any laws, although he acknowledged that the pair's versions conflict.

"It's just a very unfortunate thing," the defense attorney said.

Sivulich's guilty plea was accepted by Judge S. Mark Johnson of Bountiful after Roy Judge Roger Dutson excused himself because he is acquainted with the former trooper.

Sivulich and the girl have agreed to counseling, Richards said.

Roy police said the department spent two months investigating the matter.