What factor we can consider misrepresentation before PR issued ??
To be clear, misrepresentation is about giving IRCC false information, information known to be false and is something that can influence the outcome of the application.
In a sense, and there have been some such cases, the false information can be the representation that the relationship is a genuine marriage when in FACT the marriage was entered into for the purpose of obtaining status in Canada. That is, the fact of it being a marriage of convenience shows there was misrepresentation, a misrepresentation that the application was based on a genuine marriage.
And, in SOME cases, how quickly the relationship broke down once the individual actually has status in Canada has been both a triggering factor, and indirect evidence of the misrepresentation.
BUT generally misrepresentation cases are based on specific statements of fact which were NOT true when made and were known to not be true.
As I previously observed, if you know someone made material misrepresentations (that is, that they lied) in the process of applying for PR, that should be reported to IRCC. Simply and directly. A report stating that [name] claimed fact XYZ in an application for PR when that fact was not true. The report should be specific, not a generalized complaint about the person, except enough general information to identify who, what, and when. Make the report and then FORGET about it unless IRCC asks for more information or more input.
Anyone involved in the situation should NOT pursue making a report for revenge. It should NOT be about punishing someone for a breakdown or failure in the relationship. Actual FRAUD should be reported, of course. Just like knowledge of any crime should be reported. But an allegation of crime should NEVER be made to punish the other person. An allegation of crime should only be made because there is a good faith belief, based on actual knowledge, that a crime has been committed.