A Westmoreland County judge on Tuesday rejected a defense bid to dismiss charges against a Rostraver man accused of using a date rape drug to sexually assault an unconscious woman in her home last year.

Nathaniel Tire Johnston, 34, is charged with rape and other offenses based on allegations made by a 29-year-old woman who said she was assaulted while asleep on a sofa in August. The woman claimed she found Johnston, a man she said was a friend and onetime sexual partner, in her home when she returned from a night out at local casino.

She testified she briefly awoke to find Johnston on top of her but was unable to stay awake during the encounter and later suspected she was under the influence of a drug. The woman said she previously used the drug prior to another sexual encounter with Johnston, but did not consent to its use or the sexual activity during the encounter in August.

Johnston initially denied having a sexual encounter with his accuser but later confessed, testified state police Trooper Marc Chieffallo.

Assistant Public Defender Amanda Shields argued prosecutors could not prove Johnston drugged the alleged victim. She suggested the accuser had a stash of the drug in her home to sell. No drug test confirmed the presence of a date rape drug, she said.

Common Pleas Court Judge Scott Mears ruled there was enough evidence for the case to go to trial.

“The commonwealth has an extremely low burden at this point, so I have to accept the victim’s testimony at this stage of the case. At trial, the opposite is true. The victim testified she didn’t take (the drug) but knew what it felt like. The defendant had motive to use it and there is evidence of consciousness of guilt through his initial denial to the officer,” Mears said.

A date for Johnston’s trial has not been set.