The Bush administration should release all of Supreme Court nominee Samuel Alito's internal Justice Department documents before confirmation hearings begin next month, Senate Democrats said Tuesday.

The documents "will be important in evaluating Judge Alito's nomination," the eight Judiciary Committee Democrats said in a letter to Attorney General Alberto Gonzales.

Alito worked for the solicitor general's office in 1981-1985, and also as deputy assistant U.S. attorney general from 1985-1987 before becoming a federal prosecutor and judge. President Bush picked him for the Supreme Court in October.

"There are currently thousands of public documents on Judge Alito's extensive 15-year judicial record that provide more than sufficient evidence into his judicial philosophy," Justice Department spokesman Brian Roehrkasse said. "Furthermore, as a number of former solicitors general from both Republican and Democratic administrations have noted, releasing internal ... documents would significantly compromise the ability of the solicitor general's office to obtain advice necessary in defending the American people in legal proceedings."

The National Archives already has released some of Alito's solicitor general documents, including a legal memo in which he urged fellow Reagan administration lawyers to seek the gradual erosion of abortion rights rather than mount an all-out repeal of Roe v. Wade, the 1973 ruling establishing a constitutional right to abortion.

Those documents "make it clear that we and the American people could learn much about Judge Alito's judicial philosophy and legal thinking" from the remaining documents, the Democrats said in Tuesday's letter.

If confirmed by the Republican-controlled Senate, the 55-year-old federal appeals court judge would succeed retiring Justice Sandra Day O'Connor. She has often been the swing vote on abortion, the death penalty, affirmative action and other contentious issues.

The Senate hopes to hold a final vote on Alito's confirmation by Jan. 20.

Several environmental groups, including Earthjustice, Greenpeace, the Sierra Club and Friends of the Earth, called Tuesday for Alito's defeat. Alito is the first nominee these groups have opposed since Robert Bork. "The more one learns about his positions, the clearer it is that he's the wrong choice," said David Bookbinder of the Sierra Club.