There are times, nevertheless, when one may lawfully make known the offense of another even though as a consequence the trust hitherto reposed in him be rudely shaken or shattered. If a person’s misdoing is public in the sense that sentence has been passed by the competent legal tribunal or that it is already notorious, for instance, in a city, then in the first case it may licitly be referred to in any place; in the second, within the limits of the town, or even elsewhere, unless in either instance the offender in the lapse of time should have entirely reformed or his delinquency been quite forgotten.
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The employment of this teaching, however, is limited by a twofold restriction. (1) The damage which one may soberly apprehend as emerging from the failure to reveal another’s sin or vicious propensity must be a notable one as contrasted with the evil of defamation. (2) No more in the way of exposure should be done than is required, and even a fraternal admonition ought rather to be substituted if it can be discerned to adequately meet the needs of the situation. Journalists are entirely within their rights in inveighing against the official shortcomings of public men. Likewise, they may lawfully present whatever information about the life or character of a candidate for public office is necessary to show his unfitness for the station he seeks.
newadvent.org/cathen/04757a.htm
