Mental disability and the justice system

or a long time, people with mental disabilities were isolated from mainstream society. Today they are becoming increasingly integrated, becoming full-fledged citizens and responsible in the eyes of the law. Now the mentally disabled, in particular those with a slight or borderline deficiency, may end up facing the criminal justice system as a defendant or offender. Yet, numerous studies have shown that these people are particularly vulnerable in the face of the penal process. Their specific needs are little known, and they may be discriminated against.

The research team Déficience intellectuelle, troubles envahissants du développement et intersectorialité (Mental Disability, Pervasive Developmental Disorder and Intersectoriality), directed by Céline Mercier from Université de Montréal, has carried out three research projects into this question, in partnership with stakeholders from the sectors involved, including a legal psychiatry institution, Quebec Correctional Services and the Centre de réadaptation en déficience intellectuelle Gabrielle-Major.

The team's work has shown the magnitude of the organizational barriers between the justice and rehabilitation systems, and the urgency of overcoming these barriers. It has also allowed the identification and characterization of people with mental disabilities found in prisons or psycho-legal situations, and provided a better understanding of their path through the criminal justice system and their reception in prison after committing a minor offence, as well as the decision of whether to prosecute behaviour that may be considered to be a minor offence.

The knowledge obtained through this work has been widely discussed with the various stakeholders. It has been the subject of numerous presentations and a cross-training session bringing together participants from all of the authorities involved. These exchanges led to a progressive definition of parameters for good practice and the establishment of courses of action in the face of a challenge that involves crossing boundaries and building bridges between public safety, justice, social services and rehabilitation.


Équipe de recherche Déficience intellectuelle, troubles envahissants du développement et intersectorialité


Céline Mercier, Université de Montréal

Regular members

  • Marjorie Aunos, Centre de réadaptation de l'ouest de Montréal
  • Jacques Bellavance, Centre réadaptation Gabrielle Major
  • Gilles Côté, Université du Québec à Trois-Rivières
  • Anne Crocker, Université McGill
  • Yves Lachapelle, Université du Québec à Trois-Rivières
  • Diane Morin, Université du Québec à Montréal
  • Katherine Moxness, Centre de réadaptation de l'ouest de Montréal