A sexual assault charge against a 56-year-old Plymouth man was dismissed Tuesday after the prosecution acknowledged there was not enough evidence to prove the case, a defense attorney said.

John E. Schoerner, of N6107 River Heights Drive, had been charged with second-degree sexual assault of a child, but that was dismissed on a motion by the prosecution, said defense attorney John Schiro. He said testimony from other people present the day of the alleged assault established that Schoerner did not have inappropriate contact with the 15-year-old girl.

“It was just really inconceivable that he could have done this given all the people around,” Schiro said. “Her recollection of the event was very sketchy, and indeed changed very significantly from when she first told it to her mother to when she told police.”

The girl had claimed Schoerner touched her inappropriately after she passed out from drinking heavily during a party at Schoerner’s home, according to a criminal complaint. Schiro said Schoerner helped the girl into the shower after she threw up on herself but did not touch her inappropriately aside from some potential “incidental” contact.

The charge had previously been dismissed by Judge Timothy Van Akkeren during a preliminary hearing in March 2008, but it was re-filed a month later. The new charge was dismissed by Judge Gary Langhoff.