A federal judge on Monday upheld subpoenas to compel testimony of journalists at NBC News and Time magazine in a special prosecutor's probe into whether Bush administration officials illegally leaked a covert CIA officer's name to the news media.
Plame is the wife of Joe Wilson, a former ambassador who was asked by the CIA to travel to Niger in February 2002 to check reports that Iraq had tried to buy enriched uranium from the African country.
A newspaper columnist disclosed Plame's identity in July last year and Wilson accused the Bush administration of having leaked the information to pay him back for having publicly taken issue with the president's uranium claim.
Disclosing the identity of a clandestine intelligence officer is a federal crime as is leaking classified information to the media.