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Complaint concerning a prohibited practice

Workers may file a complaint if they believe they are the victim of sanctions, discriminatory measures or reprisals prohibited by law on the part of their employer.

Recognizing a prohibited practice

A prohibited practice is when a worker is dismissed, suspended, transferred or has any other sanction imposed on them because they:

Dismissal because a worker is pregnant

Jacynthe just found out she is pregnant. She tells her employer the good news and discusses her maternity leave with them. A few days later, she finds out she has been dismissed. Jacynthe could file a complaint concerning a prohibited practice. An employer may not dismiss a worker because she is pregnant.

Threat of dismissal following an absence for parental obligations

François has to take time off work because his child's daycare is closed due to a plumbing problem. His employer threatens to dismiss him. If dismissed, François could file a complaint concerning a prohibited practice. An employer may not dismiss a worker who is absent from work to fulfil family or parental obligations.

How the complaints process works

Filing a complaint

A person who wishes to file a complaint can complete the File a complaint questionnaire. If the complaint is admissible, they will be directed to the appropriate instructions for filing an official complaint.

There are several steps in the complaints process. Throughout the process, the person who filed a complaint is asked to cooperate with various CNESST officers, in particular by providing the information and documents requested.

Representation of trainees

Trainees who complete 1 of the following 2 types of training periods may be represented:

  • training period required to obtain a permit to practice issued by a professional order
  • training period that is part of a study program

With their consent, a complaint may be filed on their behalf by:

  • a non-profit student rights organization
  • a pupil or student association
  • a group of pupil or student associations


To be admissible, the complaint must be filed within 45 days of the day of the dismissal or the sanction. In the case of a worker who is forced to retire or who has a sanction imposed on them after refusing to retire, the time limit is 90 days.

Analysis of the complaint

Once the complaint is filed, the CNESST contacts the person who filed the complaint to verify whether the complaint is admissible. Among other things, it makes sure that:

  • the grounds for the complaint are provided for by law
  • the person who files a complaint is protected by law
  • their employer is subject to the ALS or, if applicable, the respondent is subject to the act the person’s recourse is based on
  • the person has no other recourses under a collective agreement or other act
  • the complaint was filed within the time limit prescribed by law

If the complaint is admissible, the CNESST notifies the person who filed the complaint and checks whether the disagreement can be resolved by communicating with the employer, for example by explaining the standards that apply. If this is not possible, a number of options are provided for to try to resolve the situation.

If the complaint is inadmissible, the CNESST notifies the person who filed the complaint and explains the reasons. If the person disagrees with the decision, they have 30 days to contest it by completing the Application for review of decision form. The CNESST has 30 days to respond.


When a complaint is filed, the CNESST offers a free mediation service.

If mediation is refused or if an agreement cannot be reached, other options are proposed to try to resolve the situation.

Transfer of the file to the CNESST’s legal affairs department


A complaint concerning a prohibited practice is heard by the Tribunal administratif du travail. If the judge determines that the complaint is founded, they may order the employer to:

  • reinstate:
    • the worker in their job with all their rights and privileges
    • the trainee in their training period with all their rights and privileges
  • pay the worker or trainee an indemnity equivalent to the wages and benefits lost as a result of the sanction received
  • amend the worker's or trainee's disciplinary record
  • put accommodation measures in place to protect a trainee, to limit the impact on their training period or to allow them to successfully complete their training period
  • comply with any other measure to safeguard the rights of a trainee
  • render any other decision they consider fair and reasonable in the circumstances

In the case of a domestic worker or a babysitter or a care provider, the Tribunal administratif du travail judge may only order the employer to pay them an indemnity for the wages and other benefits they did not receive as a result of their dismissal.

Measures adapted to the particular situations of trainees may be imposed by the Tribunal administratif du travail to remedy the harm that may have been caused to them.

Any employer, educational institution or professional body that contravenes the Act to ensure the protection of trainees in the workplace is liable to a fine.

Laws and regulations

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