Linda Doherty's autistic son, Marc, is a student at Rotenberg and was being treated with shock therapy for his aggressive behavior.
"My son is not attacking people, so people can work with him without fear of being physically harmed," said Doherty. "He's able to go on field trips and go out into the community. I think that is a success."
Since the incident at Rotenberg was reported more than three months ago, representatives from both the school and the Department of Early Education and Care told ABC News that the center has undergone several changes.
"[Rotenberg] implemented certain measures and protocols for the safety of their children as part of their short-term response," said Early Education and Care spokeswoman Cindy Campbell. "They structured their monitoring department to include additional supervision for those working directly with the student and instituted a new [and more secure] telephone system."
Electric shock therapy is still being administered by the school, but it was temporarily suspended from being used in the residential areas, according to Campbell. The Associated Press contributed to this story.