Karen Thorndyke said since 2006, five different schools in Mississauga and Brampton punished her son, Christian, for outbursts or misbehaviour by placing him in small, locked rooms the board calls alternative learning spaces.
She said sometimes the boy soiled himself in the room because he wasn’t allowed to leave to use the bathroom.
"You don't want to believe it. You don't want to think that these spaces are being used in which ways they shouldn't be,”"Thorndyke said.
She said she's worried about bringing her son to school now, and her son said he feels scared and anxious as well.
Peel District School Board said it can’t disclose any information about the case in a news release sent to CBC News.
"We remain deeply committed to supporting this child and his family," the statement said.
Margaret Spoelstra of Autism Ontario said she was surprised by the lawsuit, as the Peel board has been a "leader" when it comes to educating students with autism in the past.
The Thorndykes say they hope the lawsuit will make the board rethink its policy of placing students into the so-called isolation rooms.
"I wish they would get rid of them altogether," Karen Thorndyke said.
The CBC Toronto's Matt Llewellyn has more on this story in the video above.
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