WASHINGTON, Feb. 1 — The Bush administration is rebuffing requests from members of the Senate Judiciary Committee for its classified legal opinions on President Bush's domestic spying program, setting up a confrontation in advance of a hearing scheduled for next week, administration and Congressional officials said Wednesday.

The Justice Department is balking at the request so far, administration officials said, arguing that the legal opinions would add little to the public debate because the administration has already laid out its legal defense at length in several public settings.

But the legality of the program is known to have produced serious concerns within the Justice Department in 2004, at a time when one of the legal opinions was drafted. Democrats say they want to review the internal opinions to assess how legal thinking on the program evolved and whether lawyers in the department saw any concrete limits to the president's powers in fighting terrorism.