Via Jim Romenesko's MediaNews:

Miller is in jail because she pledged confidentiality to a rat

That's Don Wycliff's view. He writes: "If we don't want to get caught up in situations like [Judith Miller's] and Time magazine's Matt Cooper's, we need to become far more discriminating about when and to whom we promise anonymity. More fundamentally, I think we need to become far more realistic about the 1st Amendment, quit talking about it as if it were some ultimate trump card that puts journalists above the law and beyond accountability, and recognize it for what it is: a constitutional tool that belongs to all the people for the protection of the right of all the people to be informed about the working of their government."

There's even more that Romenesko didn't quote, and it's all very good:

Most important, I think we need to rethink our current headlong rush to trade away the 1st Amendment in its fullness for the protection that a federal "shield law" would confer upon some tiny fraction of "the people" who call themselves journalists.

[…] Miller is in jail not because she refused to divulge the name of a Deep Throat, who saw the constitutional order of the nation imperiled and so became a confidential source to Bob Woodward and Carl Bernstein in their Watergate reporting.

Miller is in jail because she promised confidentiality to a rat--someone who was trying to get back at a political critic of the current administration by revealing to the world that the critic's wife was a secret agent of the United States government. In other words, the source chose to play politics by playing with the life of an American spy, not to mention all of her contacts.

I particularly like this answer to the assertion that reporters have to shield rats also because otherwise they won't get information from people who only turn out to be rats later:

We in the news business can argue that the nature of the source shouldn't matter, that the only thing that matters is that we made a promise and so we're bound to keep it.

But the fact is that it matters to the American people, who know the difference between a poodle and a polecat and whose reactions to these cases determine whether the sort of exemption that Miller and Cooper tried to claim will be honored. That it has not been in this case is not just a function of the law and the judicial system, but also of the fact that the American people see nothing important at stake for the nation. In other words, they smell a rat.

[…] Last--for now anyway--we are told that this case will make it harder for reporters to get the information they need to serve the public's right to know by making sources more reluctant to speak with reporters off the record.

That's not an argument to sneeze at. The fact is that promises of confidentiality are absolutely essential in many newsgathering situations. But I dare say those situations are far fewer in number than are the number of cases in which promises are made simply as a matter of routine.

Is it absurd to think that a promise of confidentiality may engender even greater trust in the future, precisely because any source will know that it is a deeply considered action, made by a reporter who has reflected on what the cost ultimately may be?

Wycliff is the Tribune's "public editor" - the ombudsman - and he gets it. Reporters are arguing that society requires them to protect anonymous sources who burn them by using them not to expose corruption, but to propagate it. I wish I'd said it this well.