A Suffolk County grand jury has indicted a probation officer at Dorchester District Court on three counts each of rape and indecent assault and battery and one count of assault with intent to rape.

William Averill, 50, of West Roxbury, faces arraignment tomorrow in Suffolk Superior Court on the charges stemming from incidents involving a woman who'd reported to him as part of her probation for larceny in January, the Suffolk County District Attorney's office and Boston Police report.

Authorities say Averill had been on administrative leave from his job as a probation officer in Dorchester Municipal Court since an investigation began earlier this year.

Officials say that on Jan. 5, the victim, a woman in her 20s on a one-year probation term for larceny and stolen property, reported to the court's probation office as required by her sentencing:

"Averill allegedly led her into his office, where he began to touch and kiss her. She told him to stop and he did. However, later in the meeting, Averill allegedly closed the blinds in his office and sexually assaulted the victim."

Authorities say that after leaving the courthouse, the victim called a relative about the attack.

"Criminalists in the Boston Police Crime Lab were able to develop a DNA profile from evidence collected during that investigation," officials say in a statement. "Further testing by Massachusetts State Police criminalists showed that the profile matched a DNA sample provided by Averill – and excluded 99.92 percent of the male population as possible contributors."