Criminal inadmissibility can be revoked depending on the crime, the duration since you were convicted, and your behaviour since then. You might still be allowed to enter the country if you have been:
You may be allowed to enter Canada if you are rehabilitated as it removes the grounds of criminal inadmissibility. Rehabilitation means that you lead a stable lifestyle and that you are unlikely to be involved in any further criminal activity. You are eligible to apply for rehabilitation if you have committed an act outside of Canada and five years have elapsed OR if have been convicted outside of Canada and five years have passed since the end of the sentence imposed. There are two types of rehabilitation:
If 10 years have passed by since the crime was committed, an inadmissible individual could be deemed rehabilitated automatically due to the passing of time. Deemed rehabilitation refers to the state where enough time has passed since you were convicted for a criminal charge which allows you to enter the country. You may only be deemed rehabilitated if the crime committed outside Canada has a maximum prison term of less than 10 years if committed in Canada.
Individual rehabilitation refers to the state where the government of Canada believes that you will no longer commit new crimes. At least five years must have passed since the end of your criminal sentence and from the date you committed the act.
You can apply for a record suspension or a discharge to the Parole Board of Canada. Under their discretion they can either grant pardon to the offence you have committed in Canada, which may make you no longer inadmissible. If you have been granted a record suspension or discharge from any other country, you will have to check if the pardon is valid in Canada. This can be done by visiting your nearest visa office.
You can apply for a temporary resident permit (TRP) if you are inadmissible but you have a valid reason to stay in Canada and if it has been less than five years since the end of your sentence. To be eligible for a temporary resident permit, your need to enter or stay in Canada must outweigh the health or safety risks to Canadian society, as determined by an immigration or a border services officer.
There is no guarantee that you will be issued a temporary resident permit. TRP is a temporary waiver of inadmissibility that allows an individual to enter Canada who would otherwise be inadmissible. This is granted for a specific reason and for a specific amount of time, up to a maximum of three years.