A judge Wednesday dismissed the sexual assault case against a man who had been accused of assaulting a woman by taking advantage of her multiple personalities.

The case against Mark Peterson, 29, was dropped after prosecutors consulted with the woman's doctors and were told that another trial could worsen her mental condition.Peterson was convicted of second-degree sexual assault Nov. 8, but Judge Robert Hawley on Monday struck down that conviction, saying a defense psychiatrist improperly had been prevented from examining the woman.

The 27-year-old woman, known as Sarah, contended Peterson took advantage of one of her vulnerable personalities when they had sex last June in an Oshkosh park.

Hawley dismissed the case at the request of the Winnebago County District Attorney's Office.

"Our office filed a motion and supporting letter dismissing the charge," said Deputy District Attorney Vince Biskupic.

He said after the conviction was overturned, his office contacted the woman's physicians to determine whether to proceed with another trial.

"All of the doctors stated that it would not be in the best interest of the victim to go through with another trial," Biskupic said. "All of them said her mental condition likely would worsen."

He said the woman's number of exhibited personalities increased from 18 to 46 during the course of the first trial.

"She did develop a number of additional personalities during the trial, and had to be in-patient hospitalized prior to the first trial," Biskupic said.

He also said the woman's court-appointed guardian, attorney George Curtis, also agreed the woman should not be subjected to the rigors of another trial.

Biskupic said the jury's verdict in the case, although overturned on a technicality, "sent a strong message" about protecting the rights of the mentally ill.