The risk of invoking presidential prerogative

Interesting word, "privilege." Its original dictionary meaning: the rights enjoyed by the very rich. Then, there are special rights of confidentiality such as doctor-patient, lawyer-client, priestpenitent. And the privilege being contested in Washington now – executive privilege – refers to the president's right to keep confidential his deliberations in the course of formulating his policies.

President Eisenhower successfully invoked executive privilege in defying a subpoena from Sen. Joseph McCarthy. President Nixon invoked executive privilege unsuccessfully, trying to withhold the Oval Office tapes that proved to be his undoing. A unanimous Supreme Court then held that executive privilege could not prevail against a criminal investigation.

But the court did recognize that there is such a thing as executive privilege, covering presidential deliberations, stemming from the assumption that the president needs confidential and candid advice from his aides in order to be able to perform his function.

The White House and Capitol Hill may be squaring off for another test over congressional demands to investigate how the discharge of eight US attorneys came about. White House Counsel Fred Fielding (who served in the Nixon White House and the Reagan White House) implied as much in his compromise offer to congressional Democrats when he referred to "the constitutional prerogatives of the presidency."

It is hard to tell how this situation will play itself out. The closest thing to an executive power precedent in the Bush administration was a suit to compel the release of details about the Energy Task Force headed by Vice President Dick Cheney.

In a Supreme Court decision in 2004, Justice Anthony Kennedy warned that executive privilege can set "coequal branches of the government ... on a collision course."

It may be that we are getting to collision-course time again.

• Daniel Schorr is a senior news analyst at National Public Radio.