Okay, so we know that we should raise pertinent details of our sins with our confessors if necessary. But what if at the time one could not know for sure whether a certain aggravating factor was in play? I’m thinking a case where there is a significant chance that there is a factor that makes the sin even worse, where one knows that it might be the case, but one cannot tell for sure.
It is simplest and best to just confess your sins and leave judgment concerning any other factors involved to God. Remember, God wishes to restore us to himself in love. He’s not out to “get” anybody. If you confess your sins with the intention to not sin again, that is enough. If your confessor wants more details, he’ll ask for them.
An “aggravating factor” just means something that makes a sinful action significantly more serious. To use an extreme example, committing murder is already a very grave sin. Doing it for the sake of vengeance makes it graver. It would be necessary to confess that kind of aggravating circumstance.
If you are not sure if it is “significantly” graver or not, you can just say so to the priest.
I’m certain the factor, if it existed, made it more serious - but I at the time did not know for sure if that factor existed.
If you knew at the time that there was a “significant chance” that this aggravating factor applied, then I would raise it in confession. What harm can come from raising it? It will help ensure that your confession is sound and that your absolution is valid; whereas if you don’t raise it, you may later doubt its validity.