As radical as this may sound and despite what the Auditor General has found in the way of citizenship frauds, I believe once someone has been granted Canadian citizenship that grant should be absolute. Considering that anyone who has been naturalized has had their immigration papers reviewed once on applying to come to Canada and another time to become naturalized the Canadian government should have had enough time to decide whether or not to grant that person citizenship. During the course of these applications, at the immigration and citizenship stages authorities have the chance to determine whether the applicant has a criminal record and to deal with any medical or other issues that are pertinent. To allow citizens to be denaturalized is to create two classes of citizenship.
Instead, if applicants have committed criminal offenses, such as fraud, they need to be punished in Canadian jails and by Canadian courts for those offenses. Using the immigration system to penalize applicants is a misuse of government power and is done in order to circumvent the criminal standards needed to convict someone for a criminal offense, that is to say, beyond a reasonable doubt. That standard is difficult to reach, much more difficult than the civil standard of on a balance of probabilities which is the standard for denaturalization.
For these reasons I am happy to hear that the new Minister of Immigration, Refugees and Citizenship, according to the article below, is in discussion with officials to deal with loopholes discovered in the naturalization process, but I would leave matters there.