ambiguity is often applied to matters that are in fact not at all ambiguous. Sometimes the mis-application is simple carelessness, but in one application it is hard not to see a more active perversion.
Characters (fictional or actual) who are called
morally ambiguous almost never are. Instead, the label is most often applied to two sorts of characters.
One sort is morally compromised. Those characters are not all bad; they may even be mostly good; but they are discernibly not all good. The person labelling them as
morally ambiguous typically very much seems to be trying for a sort of special pleading on behalf of the character or of the moral short-comings exhibited by the character.
The other sort exhibits a combination of characteristics, some of which the audience will find attractive but some of which the person applying the label finds disagreeable, without his or her being able to make a sound case (or seemingly sound case) against those traits. By labelling the character as
morally ambiguous, the labeller is insinuating doubt without reasoned foundation. Challenged, he or she will likely deny having issued a condemnation of the characteristics against which he is directing that doubt.
In application to situations, the term
moral ambiguity is more likely to be legitimately applied than in application to characters. But calling a situation
morally ambiguous is also often an attempt to introduce by back door a special plea for bad behavior.
(One of the papers on which I am presently working, and the paper of that lot that is likely to end-up the least mathematical, compares and contrasts some decision-theoretic states that are often mistaken one for another. One sort of these states entails ambiguity. So I have been thinking about real and specious ambiguity more generally.)