WASHINGTON – A former White House aide indicted for obstruction of justice in the CIA leak investigation, I. Lewis Libby, can expect to receive a fair trial at the hands of Judge Reggie Walton, but Mr. Libby should be prepared for a lengthy prison term if convicted, according to local attorneys.

“He better win,” a defense lawyer who recently handled a drug case before Judge Walton, Douglas Wood, said. “The book on Judge Walton is he’s a pretty fair guy, but he’s a very tough sentencer.”

Mr. Libby, who is facing obstruction, perjury, and false statement charges stemming from an investigation into the leak of the identity of a CIA operative, is scheduled to make his first court appearance this morning before Judge Walton, who was assigned to the case at random.

Mr. Libby, who served as Vice President Cheney’s chief of staff before resigning following the indictment last week, is expected to plead not guilty.

Judge Walton, 56, was appointed to the federal bench in 2001 by President Bush, a fact that has buoyed the spirits of some of Mr. Libby’s supporters. In addition, Judge Walton, who is a registered Republican, served as a deputy drug tsar and White House adviser on crime policy under President George H.W. Bush. The judge received his first judicial appointment to a local court in Washington, D.C., from President Reagan in 1981.

However, a former law clerk to Judge Walton, Janene Jackson, said Mr. Libby’s allies should not count on leniency. “There might be some Republicans who thought, ‘Wow, this is great,'” Ms. Jackson said. “In his decision-making, Judge Walton is rooted in the law. His political leanings will have no impact,” she said.

Ms. Jackson, a Democrat who works for a city council member in the capital, said she and other clerks knew that the judge was affiliated with the GOP but did not consider him to be a hardcore party loyalist. “I wouldn’t say that he’s deep-rooted in Republican politics,” she said. “He loves a debate, so we would certainly have a spirited debate about political issues or ideologies. He’s never said, ‘You need to be a Republican.'”

Some of Judge Walton’s past ties have the potential to complicate any trial of Mr. Libby. When the judge served in the drug tsar’s office, he sometimes appeared at public events with Andrew Card Jr., who was deputy chief of staff at the time. In 1991, after Judge Walton clashed with a newly appoint ed drug tsar, Bob Martinez, Mr. Card offered the judge a new White House job promoting crime legislation, according to press accounts. Judge Walton accepted and later was reappointed to the local court in the capital.

Mr. Card, who is chief of staff in the current White House, could be a witness at Mr. Libby’s trial. Mr. Card is not mentioned in the indictment, but he oversaw the administration’s early response to the leak investigation and may have been present when a key memorandum related to the case was discussed.

Mr. Card did not respond to a request to be interviewed for this story.

Judge Walton’s path to the deputy drug tsar position also involved another player in the leak saga, Robert Bennett. Mr. Bennett, a Washington attorney who represents a New York Times reporter jailed for nearly three months in connection with the leak probe, Judith Miller, recommended the judge for the post, according to the man who hired him, William Bennett.

“He was actually introduced to me by my brother, the famous Bennett,” the nation’s first drug tsar, William Bennett, said in an interview yesterday. “This is a real inside baseball one, I guess.”

Asked to describe Judge Walton, the former drug tsar said, “Strong, tough judge. No nonsense guy.” William Bennett said he was not sure how the judge became a Republican. “I hope we had something to do with it,” the former drug tsar said.

Much of Judge Walton’s credibility in the drug war and as a judge comes from his own scrapes with the law as a teenager growing up in Donora, Pa., near Pittsburgh. In an interview several years ago, the judge recounted his involvement in a melee that ended with a young man’s being stabbed nine times with an ice pick.

Mr. Walton, who arrived at the fight in the company of the man who did the stabbing, later rushed the victim to the hospital. The future judge was questioned by police but never charged. “I saw my whole future flash before my eyes at that time,” the judge told the nonprofit Justice Policy Institute for a 1999 report on juvenile justice.

Mr. Walton went on to attend West Virginia State College and obtained his law degree from American University in Washington. He worked as a public defender in Philadelphia and then as a prosecutor in the capital.

Some who know Judge Walton’s story said he may not have a large reservoir of compassion for Mr. Libby, 55, who graduated from Yale and attended law school at Columbia.

Judge Walton “is not going to take a lot of junk from some large law firm,” one of the judge’s first clerks in federal court, James Beane Jr., said. “He’s also not really sympathetic to excuses from people who have always had it well.”

Judge Walton, through a spokesman, declined to be interviewed for this article.

The lawyer who has represented Mr. Libby thus far in the inquiry, Joseph Tate of Philadelphia, signaled in a statement last week that Mr. Libby plans to chalk up his allegedly false statements to a failed memory and his busy work schedule. The charges against Mr. Libby carry a maximum possible sentence of 30 years in prison, though most attorneys expect him to receive far less even if convicted on all counts.

One of the attorneys who has practiced before Judge Walton said Mr. Libby’s fortunes will dim if the judge concludes that the former vice presidential aide deliberately misled investigators. “If the judge thinks Libby was lying at certain points to the grand jury, I don’t think he’s going to like it at all,” Mr. Wood said. “He’s an ex U.S. attorney. He’s worked in that process. He’s seen people lie, impeding that process. I don’t think that will help the guy.”

Though Judge Walton is known as a talented cook, he has remained in good shape since his football days. At the local court, he would often bound up several flights of stairs, while his clerks took the elevator. The judge lives in Washington, D.C., with his wife, who is a dermatologist.