לזכות רבי משה גבריאל בן יהודית לברכה והצלחה וכל טוב סלה!
There is a mitzva to judge favorably - בצדק תשפוט עמיתך. If the person is a tzadik then he must be judged favorably even if it is a remote possibility that he is innocent. If he is a beinoni then he must be judged favorably only if it is at least 50-50 or more in his favor. If it is a far shot that he is innocent then it is correct to judge him favorably but not obligatory. If he is a rasha then there is no mitzva to judge favorably.
What is the halacha if you are in doubt as to whether he is a tzadik or beinoni and you have a case where it is a far shot that he is innocent? If he is a tzadik then you are obligated and otherwise you are not. What do you do?
Apparently, because of safek di-orasia li-chumra you should judge him favorably. On the other hand it is safe to say that MOST people are NOT tzadikim so maybe you can follow the majority and not judge him favorably. "Go after the roiv", they say in Lakewood! Nu - a dilemma...
What about an instance where you are in doubt as to whether he is a Jew or a goy. Again - the majority of people aren't Jewish so maybe you can follow the majority and there would be no obligation. But this is only if you saw him on the street where he is considered פרוש and the rule is כל דפריש מרובו פריש [when something separates you assume that it separated from the majority] while if you see him at home he is קבוע and we know that כל קבוע כמחצה על מחצה דמי [any doubt that arises in it's permanent place is considered an equal 50-50 proposition. Why? Maybe for another time:-)].
What do you think?
[Rav Avraham Genechovski ztz"l]