PLUM, Pa. — A western Pennsylvania school board has reinstated its superintendent after a law firm found no evidence he and other employees failed to properly investigate reports that teachers were having sex with students.

The board on Tuesday night voted 4-3, to reinstate Plum Borough School District Superintendent Timothy Glasspool. The vote came hours after a former student sued the district, and Glasspool, among others, for allegedly failing to properly investigate and stop the teacher convicted of having sex with her.

The board didn’t act on the status of Plum High School Principal Ryan Kociela, who is also named in the lawsuit, and didn’t immediately explain why.

Kociela and Glasspool were placed on paid leave last spring as the Allegheny County district attorney’s office issued a scathing grand jury report concluding they and other employees were more concerned about upholding the district’s image than investigating misconduct — especially that of Joseph Ruggieri, 41.

Ruggieri was the vice president of the Plum teachers’ union before he pleaded guilty to institutional sex assault and was sentenced to two to five years in state prison earlier this year.

The criminal charges stemmed from his sexual relationship with a student who was just 17 when it began. She was identified as “Jane Doe” in the federal lawsuit filed Tuesday.

The lawsuit echoes the DA’s grand jury report, even though it didn’t find enough evidence to criminally charge any district employee with violating Pennsylvania’s “mandatory reporter” law.

The law requires district employees to call police or a child welfare hotline if they have “reasonable cause to suspect” teachers are having sex with students. The grand jury couldn’t decide whether Glasspool, Kociela or other employees actively covered up the problem or were confused about the law’s requirements.

Still, the lawsuit contends Kociela covered up or dragged his feet upon learning of reports and rumors of Ruggieri’s sexual relationship with the plaintiff and at least one other student previously.

Glasspool’s home phone number has been disconnected and Kociela didn’t immediately return a message left at his home number Wednesday. District solicitor Lee Price wouldn’t comment on the lawsuit.

The board hired the Levin Legal Group, a Montgomery County law firm, to independently review the district’s investigation of teacher-sex allegations.

Michael Levin told the school board his firm found no evidence of criminal wrongdoing or that employees were encouraged to protect colleagues over the welfare of students.

Three other teachers were or are being criminally prosecuted.

Jason Cooper, 39, pleaded guilty to student sex charges and is serving up to three years in prison, while Drew Zoldak, was acquitted of charges he tried to intimidate Ruggieri’s victim by pointing her out in class.

Another former substitute teacher and athletic coach is scheduled to plead guilty next month to student-sex charges.