Snitching on friends didn't bother Immanuel Kant. Even if a murderer comes looking for someone hiding in your house, the great Enlightenment philosopher once wrote, you must tell the truth and disclose his whereabouts.
By Kant's standard, there is nothing wrong with Elia Kazan's naming names to the House Committee on Un-American Activities in 1952. He may have betrayed his associates and condemned them to Hollywood's blacklist, but he was telling the truth. And if truth-telling trumps loyalty, Linda Tripp can only be admired for revealing Monica Lewinsky's secrets to Ken Starr.
But truth-telling isn't the only moral virtue. It often wrestles, and rightly so, with the virtues of loyalty and solidarity. We often assert these particularist virtues with a guilty conscience, as if standing by our friends is a kind of prejudice that puts us outside the realm of moral principle. But loyalty and betrayal are moral categories, not just emotional ones. Without them, we would be incapable of friendship or patriotism.
If truth-telling and loyalty are competing moral principles, how can we determine which principle to follow under what circumstances? The answer is that we must be judgmental. We must weigh the moral importance of the cause that truth-telling or loyalty would advance.
Consider the case of Elia Kazan. In his great movie On the Waterfront, he portrayed the informant in a favorable light. The longshoreman played by Marlon Brando (a promising boxer who "could have been a contender") testifies against the nefarious mob leader who runs the union. But in doing so, he violates the ethic of the waterfront and is ostracized as a stool pigeon until the mob's hold on the union is broken in the end.
Kazan reportedly viewed On the Waterfront as a metaphor for his own moral dilemma. But just as Kazan's critics are wrong to claim that informing is always wrong, so Kazan was wrong to imply that informing is always right. The figure in the movie was a moral hero because he told the truth in a just cause; his betrayal was of an evil, powerful mob. Kazan's own truth-telling was more morally complicated. On the one hand, solidarity with a Communist Party apologetic for Stalinism is nothing admirable. On the other hand, neither is delivering relatively powerless associates into the hands of blacklisting McCarthyites. The hero of On the Waterfront was a stool pigeon whose truth-telling advanced the cause of justice. The same cannot be said of Kazan's testimony (which, incidentally, is no reason to deny him an Academy Award).
The same point emerges if you consider the two figures whose famous betrayals helped unravel the Clinton and the Nixon scandals--Linda Tripp and John Dean. Both are unsavory characters whose testimony led to revelations of presidential misdeeds. What makes John Dean's betrayal of Richard Nixon more admirable than Linda Tripp's betrayal of Monica Lewinsky has mainly to do with the fact that Dean exposed wrongdoing that threatened the republic and the constitutional system, whereas Tripp exposed less grievous wrongs. Power makes a difference, too. In betraying the confidences of Monica Lewinsky, Tripp was snitching on a relatively powerless figure whose friend she had claimed to be, whereas Dean was snitching on his boss, the figure at the center of the Watergate coverup.