Also on Tuesday, the Pentagon referred a Democratic request for an internal review on the subject to the National Security Agency's inspector general.

In a three-paragraph letter, Justice's Inspector General Glenn Fine forwarded the request to the department's Office of Professional Responsibility, which reviews allegations of misconduct involving employees' actions when providing legal advice.

President Bush's decision to authorize the NSA to monitor _ without warrants _ people inside the United States has sparked a flurry of questions about the program's legal justification.

Bush and his top aides say the activities of the nation's largest spy agency were narrowly targeted to intercept calls and e-mails of Americans and others inside the United States with suspected ties to al-Qaida.

But a growing chorus of legal experts from both parties are raising doubts about Bush's authority to order such monitoring on U.S. soil and questioning whether the White House should have sought changes in law.

Congress also plans to investigate. As part of its work, the House and Senate intelligence committees will soon hear from former NSA officer Russell T. Tice. The whistleblower told lawmakers in Dec. 16 letter that he had information about "probable unlawful and unconstitutional acts" involving the NSA director, the defense secretary and other officials as part of highly classified government operations.

ABC News reported Tuesday night that Tice claims to be one of the dozen sources who spoke to The New York Times about monitoring programs. The newspaper declined to comment, spokeswoman Catherine Mathis said.

Over three dozen House Democrats _ led by Rep. Zoe Lofgren, D-Calif., a member of the Judiciary and Homeland Security committees _ have also requested separate investigations by Justice's inspector general, the Pentagon's inspector general and Congress' watchdogs at the Government Accountability Office.

A senior Defense Department official, who spoke on condition of anonymity because the information was not yet public, said the Pentagon's watchdog will not do a review because the NSA's inspector general is "actively reviewing aspects of that program."

Lofgren said she thought the Pentagon's watchdog was best suited for the work.

She and a number of her colleagues also wrote to Fine on Monday, saying his decision not to open an inquiry was wrong. Under the Patriot Act, the Democrats said, his office is designated as the "one entity responsible for the review of information and complaints regarding civil rights and civil liberties violations" by Justice officials.

Deputy Inspector General Paul Martin said neither the Patriot Act nor the law that governs all inspectors general gives Fine jurisdiction to look into the attorney general's actions concerning the electronic surveillance program. Issues dealing with that legal authority are "jurisdiction of the department's Office of Professional Responsibility," Martin said.