A former employee at Taylor Manor Hospital in Ellicott City pleaded guilty yesterday to charges stemming from a sexual assault against a 15-year-old patient there last summer.

Alvin Tyrone Williams, 40, described by a prosecutor as a psychiatric nurse counselor, pleaded guilty to attempted third-degree sexual offense, a crime that carries a maximum 10-year prison term. Under a plea agreement, prosecutors have agreed to cap their request for prison time at five years, said Senior Assistant State's Attorney Mary V. Murphy.

Sentencing, before Howard Circuit Judge Lenore R. Gelfman, is set for Sept. 5.

Williams, who is married, worked at the psychiatric hospital for two years and is now employed elsewhere, his lawyer, Roland Walker, said. Williams has an "impeccable" background and is in psychiatric counseling, Walker said.

According to a statement of facts that Murphy read into the record yesterday, the teen-ager had been a patient at the psychiatric hospital for two days at the time of the incident.

The girl told authorities that Williams would ask "inappropriate questions" about her sexual activities, tell her she was "sexy" and ask her to "flash" him, Murphy said.

On July 8, while the girl's roommate was away from the room, he walked in and initiated sexual contact between them, Murphy said.

Investigators found Williams' DNA in a sample taken from a hospital gown used by the girl, Murphy said.

In a police interview, Williams admitted having a sexual encounter with the girl, Murphy said.

Walker said that while Williams admitted to touching the girl, he said no force was used.