A Superior Court judge has ruled a lawsuit alleging the Ontario government violated the rights of inmates by placing them inappropriately in solitary confinement can proceed as a class action.

The province didn't oppose certification of the 600-million dollar action.

The representative plaintiff maintains his already fragile mental health was exacerbated by stints in segregation.

The suit includes inmates diagnosed with severe mental illnesses such as schizophrenia or psychosis, who served time in segregation in provincial facilities since January 1st, 2009.