Supreme Court nominee John G. Roberts Jr. once expressed some agreement with conservatives who opposed entering an international anti-genocide treaty, saying that foreign governments might try to use it to prosecute the United States for its military actions overseas.

But Roberts, then a young White House lawyer, ultimately urged President Ronald Reagan to sign it, arguing that to do otherwise would be a public-relations embarrassment on the world stage.

His arguments -- which could provide fodder for Democrats pressing for more clarity on the nominee's views on U.S. obligations toward international law -- were outlined in a memo that was among 18,000 pages of White House records released yesterday by the National Archives.

The documents, which come on top of tens of thousands of pages already released from Roberts's files, are probably the last that will be made public before the start of his confirmation hearings Tuesday.

The papers include insights into his thinking on a variety of issues -- including the insanity defense, the invasion of Grenada, international trade and the spraying of herbicides on marijuana crops.

A witness list released yesterday by Democrats on the Senate Judiciary signaled their intent to focus the hearings on the civil rights record of Roberts, who was appointed to the U.S. Court of Appeals for the District of Columbia Circuit two years ago. Like the administration he served in the 1980s, Roberts was a staunch opponent of affirmative action, generally took a narrow view of civil rights laws and fought efforts to expand anti-discrimination protections.

Among the witnesses the Democrats will call during the four days of scheduled hearings are several civil rights leaders, including the executive director of the Leadership Conference on Civil Rights. Democrats also plan to call witnesses who have advocated for the rights of the disabled and women.

Carol M. Browner, the Environmental Protection Agency head under President Bill Clinton, will testify, as will a representative from Planned Parenthood, an abortion rights group and former Nixon White House counsel John Dean, who has advocated for the release of memos from Roberts's post as principal deputy solicitor general under the George H.W. Bush administration. The White House, citing attorney-client privilege, has refused Democratic requests to release the documents.

Also yesterday, the AFL-CIO wrote a letter to Senate Judiciary Chairman Arlen Specter (R-Pa.) expressing "grave concerns" about Roberts. Citing Roberts's record on civil rights and other issues, President John J. Sweeney urged committee members to engage in "vigorous and extensive questioning" of Roberts.

But to the disappointment of some Democrats, the union federation did not explicitly oppose his nomination, which has won support from the business community in the form of an endorsement by the U.S. Chamber of Commerce.

Yesterday's document release, which included some duplicative material, came after National Archives staff realized many of Roberts's papers had been filed under a previously unknown coding system.

Roberts's Sept. 4, 1984, memo on the Genocide Convention could draw the interest of Democrats, who have already put him on notice that they intend to question him on the Bush administration's approach to terrorism.

As a federal appeals court judge, Roberts upheld the use of military tribunals to try detainees suspected of terrorism. The Judiciary Committee's ranking Democrat, Sen. Patrick J. Leahy (Vt.), has said he told Roberts to expect questions on whether President Bush tried to set himself "above the law" in setting torture policy for terrorism suspects.

Leahy has pointed to a controversial memo written by current administration lawyers that gave advice on when torture is appropriate and argued that the president had the right to issue orders violating the Geneva Convention and other international laws. Leahy has said he hopes to get Roberts's opinion on the memo.

The Genocide Convention treaty, which committed nations to preventing and punishing genocide, had been signed by President Harry S. Truman in 1948 but had languished in the Senate without ratification because of conservative opposition.

Roberts noted in his memo that the objections included the argument that the treaty "internationalizes" criminal law, that it could force Americans to stand before an international tribunal, that violent nations would ignore the treaty while hostile ones could use it for "propaganda" purposes, forcing the United States to go before the tribunal because of its actions in Vietnam or other countries.

"These objections are not unfounded," Roberts wrote. But he added that "a consensus has evolved that they are outweighed by the propaganda windfall our failure to ratify the convention has already afforded our international opponents."

The Reagan administration later declared its support for the convention. The debate, though, has resonance today, since Bush has adamantly opposed subjecting U.S. soldiers to international courts.

In April 1985, the head of the White House Fellowship program asked for guidance when the staff writer for the program's alumni newsletter penned a favorable review of a book criticizing the administration's call for reform of the insanity defense.

In a memo to his boss Fred F. Fielding, Roberts gave his own review. "[Author Lincoln] Caplan documents how infrequently the insanity plea is invoked, and how rarely it is successful, but does not note that, even rarely invoked, the plea imposes staggering costs on the judicial system and, since it is often invoked in celebrated cases, has an effect on public confidence in the law far out of proportion to the number of cases in which it figures."

But he advised against making any changes. "The surest way of according prominence to the book and the review would be to attempt to block the review."

In a Jan. 12, 1984, memo, Roberts raised "serious legal questions" about the president's intended radio address announcing the recall of the U.S. ambassador and suspension of all trade with Nicaragua following the mysterious slaying of a U.S. service member there.

Roberts noted that the suspension of trade required an "unusual or extraordinary threat" and a consultation with Congress. A few months earlier, Roberts chafed at the president's planned remarks at a reception for medical students rescued in the Grenada invasion, objecting to the scripted comment that "we didn't invade Grenada, we rescued Grenada."

"Of course we invaded Grenada, as we invaded France on D-Day," Roberts wrote in a Nov. 4, 1983, memo.

Staff writer R. Jeffrey Smith, researcher Bobbye Pratt and news aide Elliott Postell contributed to this report.

Researcher Ray Wilson at the Ronald Reagan library in Simi Valley, Calif., examines some Reagan-era documents relating to John G. Roberts Jr.Supreme Court nominee John G. Roberts Jr.'s signature is seen on a letter he wrote as associate White House counsel during the Reagan administration.