Some unauthorized disclosures of classified information in the press can serve a constructive purpose, Sen. John McCain allowed. And so he expressed support for a pending press “shield” law that would increase reporters’ legal protection against compulsory disclosure of their confidential sources.

“Despite concerns I have about the legislation, I have narrowly decided to support it,” he told the Associated Press Annual Meeting on April 14.

The bill, the Free Flow of Information Act, is co-sponsored by Sen. Barack Obama and has also been endorsed by Sen. Hillary Clinton. But Sen. McCain’s support is noteworthy because it places him directly at odds with the Bush Administration, which strongly opposes the measure.

Even more interesting is the way in which McCain framed the issue:

“The shield law is, frankly, a license to do harm, perhaps serious harm. But it is also a license to do good; to disclose injustice and unlawfulness and inequities; and to encourage their swift correction.”

“I know that the press that disclosed security secrets that should have remained so also revealed the disgrace of Abu Ghraib.”

In other words, according to Sen. McCain, there are bad leaks of classified information and there are good leaks of classified information. (The leaked Army investigative report on Abu Ghraib [pdf] was classified Secret).

This comparatively nuanced view of unauthorized disclosures is a significant departure from the Bush Administration’s categorical view that any disclosure of classified information is unacceptable. And it provides some common ground for considering both disclosure and voluntary non-disclosure of classified information by the press.

The text of Sen. McCain’s April 14 speech is here.

The Washington Post editorialized today in favor of the press shield bill, which is also supported by press advocacy organizations such as the Reporters Committee for Freedom of the Press. Jack Shafer in Slate.com demurred.