The retired New York judge who is President Bush’s pick to be the next attorney general, Michael Mukasey, will face his first test in the confirmation process today, when he meets with the chairman of the Senate Judiciary Committee, Patrick Leahy.

Whether Judge Mukasey is ultimately confirmed will depend partly on whether Democrats see him as independent from White House policy positions and partly on matters entirely unrelated to the nominee — such as the White House’s response to ongoing Senate investigations of Attorney General Gonzales.

The Senate majority leader, Harry Reid, yesterday praised President Bush for avoiding “another partisan administration insider” in picking Judge Mukasey, whom the Democratic senator described as having “a reputation for independence.”

“But there should be no rush to judgment,” Mr. Reid also said.

On Capitol Hill, there is a rush, however, to learn more about Judge Mukasey, who spent 19 years on the federal bench in Manhattan. Despite his handling of high-profile cases ranging from President Bush’s detention of Jose Padilla to the fate of the life insurance policies held by those murdered in the Holocaust, Judge Mukasey was never well-known beyond downtown Foley Square, home to Manhattan’s federal courts.

“An obscure district judge” is how Judge Mukasey once characterized himself in a decision he issued in the largest terrorism prosecution in American history.

Indeed, even in New York, Judge Mukasey was frequently mistaken for someone else. That may have been because of the group of bodyguards that followed him at all times after the 1995 terrorism trial he oversaw. His armed entourage has been confused for President Clinton’s security detail, and the judge himself has been mistakenly identified as King Hussein of Jordan, the Southern District of New York’s chief judge, Kimba Wood, recalled last year in a speech honoring Judge Mukasey.

A close look at Judge Mukasey’s judicial record indicates that many of the judge’s positions on national security matters — such as the USA Patriot Act and detention of terror suspects without charges — coincide closely with the Bush administration’s positions.

“He’s very conservative, but he’s absolutely his own man,” a leading civil rights attorney who is a law professor at New York University, Burt Neuborne, said.

“In all of our cases, he raised the bar on the prosecution,” a former U.S. attorney for the Southern District of New York, Mary Jo White of Debevoise & Plimpton LLP, said. “He ruled right down the middle on the issues.”

Those who seek to portray Judge Mukasey as independent-minded are expected to publicize a case that he decided just days before he left the bench last year to return to private practice. In U.S. v. Lindauer, Judge Mukasey refused the government’s request that he order a woman, diagnosed as paranoid and delusional, to take psychotropic drugs in order to be competent enough to stand trial. The defendant, Susan Lindauer, is charged with serving as an agent of Saddam Hussein. Although the case was being prosecuted by the U.S. attorney’s national security and terrorism bureau, Judge Mukasey questioned the government’s interest in prosecuting the case.

“Even lay people recognize that she is seriously disturbed,” he ruled. “Lindauer has been found to pose a threat neither to herself nor to others.”