WASHINGTON — William Hubbs Rehnquist, the 16th Chief Justice of the United States, died last night at his home in Arlington, Va. He was 80.

Rehnquist, who had been suffering from thyroid cancer since last October, had managed to lead the court through its last term, which ended in June. But he went through "a precipitous decline in his health in the last couple of days," Supreme Court spokeswoman Kathy Arberg said.

A conservative stalwart appointed as associate justice by President Richard M. Nixon in 1972, Rehnquist was elevated to chief justice in 1986 by President Ronald Reagan. His 33-year tenure on the court was one of the longest and most influential in the institution's history, as he spearheaded a rightward move at the court — first as a lone dissenter, then later as the leader of a five-justice conservative majority.

Rehnquist leaves a towering legacy. As a young lawyer in Phoenix in 1957, he declared a personal war of sorts against the Supreme Court, then headed by Chief Justice Earl Warren. Rehnquist gave a speech blasting Warren and Justice Hugo Black as "left-wing philosophers." He published a magazine article blaming the Warren court's liberal drift on the "political cast" of the justices' law clerks.

Rehnquist's effort to roll back the modern liberal tide would take him to Arizona Republican Senator Barry Goldwater's ill-fated 1964 presidential campaign, to the Nixon administration Justice Department and eventually, in 1972, to the court itself.

After 33 years there — the last 18 of them as chief justice — Rehnquist could have claimed to have fought Warren to a draw.

Key Warren Court rulings — among them the ban on school prayer and the Miranda case guaranteeing a suspect's "right to remain silent" — have survived. And the post-Warren decision Roe v. Wade, the abortion rights ruling that Rehnquist tried to overturn, also seems entrenched, for now.

Yet the Rehnquist Court has strengthened the legal position of the police, paved the way for swifter executions, defined constitutional limits on federal power and permitted indirect government funding of religious schools.

LED COUNTERREVOLUTION

Though Rehnquist and his fellow conservative justices often acted in the name of judicial restraint, it is perhaps more accurate to say that they showed an active court could serve conservative ends as well as liberal ones.

During Rehnquist's tenure, the Supreme Court has arguably expanded its role in American life, frequently striking down laws passed by Congress, subjecting the president to independent counsel investigations and private lawsuits and, in 2000, settling a presidential election.

Though the full scope of the Rehnquist counterrevolution is still much debated, legal scholars already rank him among the court's great chief justices.

"When the history of the Supreme Court in the 20th century is written, there will be two great chief justices: Earl Warren and William Rehnquist," said Mark Tushnet, a professor at the Georgetown University Law Center. "Both presided over courts that changed the law in a very dramatic way."

Still, as his tenure concluded, there was a sense at the court that Rehnquist's most influential days were already behind him. In recent terms, he suffered defeats on issues he cared deeply about, such as affirmative action in university admissions, which the court sustained, and state sovereignty and individual property rights, which it curbed. He cast a vote but expressed no written opinion in the court's historic decision last year granting federal court access to prisoners at Guantanamo Bay, Cuba.

His impact has been blunted by his inability to win over the court's vital center, as represented by fellow Republican appointees Sandra Day O'Connor and Anthony M. Kennedy.

Yet, as Tushnet points out, the remarkable fact is that Rehnquist even came close.

"When he started, the law was tilted in a liberal direction," Tushnet added. "Now it's not really tilted in a conservative direction, but it's more of a level playing field."

ANTI-NEW DEAL

Rehnquist was born on Oct. 1, 1924, in Milwaukee and grew up in the suburb of Shorewood, Wis., where he attended public schools. When a grade-school teacher asked him what he was going to do when he grew up, the loyal son of anti-New Deal parents did not hesitate: "I'm going to change the government," he said.

He started his college education at Kenyon College in Ohio in 1942 but was drafted in March 1943. He worked as a weather forecaster for the U.S. Army Air Forces at bases in the Southwestern United States and North Africa. He would later say that his time in these warm, dry climates convinced him to settle in Arizona as a young adult.

After the war, he attended Stanford University and Stanford Law School, where he graduated first in his class in 1952. For 18 months after that, he served as a law clerk to Justice Robert H. Jackson on the Supreme Court.

Rehnquist met his future wife, Natalie "Nan" Cornell, at Stanford. They married in 1953; she worked at the CIA while he clerked for Jackson. Her death from ovarian cancer in 1991 was a devastating blow to Rehnquist.

As a young man, Rehnquist seemed to relish waging his own war of ideas against liberalism. Working for Jackson, he fired off tart memos to his boss including such remarks as, "I take a dim view of this pathological search for discrimination" against African-Americans. He suggested that "drawing and quartering" would be a more appropriate punishment than the electric chair for Julius and Ethel Rosenberg, convicted of atomic espionage for the Soviet Union.

As the court weighed Brown v. Board of Education, the landmark case that banned segregation in the public schools, Rehnquist wrote a memo defending Plessy v. Ferguson, the 1896 ruling that had established the now-discredited doctrine of "separate but equal." That decision, Rehnquist wrote, "was right and should be reaffirmed."

When challenged over the memo during his 1971 confirmation hearings, Rehnquist said it was intended to reflect Jackson's views, not his, and that he "unequivocally" supported Brown. Historians have taken a skeptical view of that explanation.

In Arizona, Rehnquist became active in the Republican Party. He served as general counsel of the state Republican committee and wrote speeches for Goldwater in his losing 1964 presidential campaign.

Also in 1964, Rehnquist was one of three people to testify against a proposed ordinance to ban discrimination in public accommodations in Phoenix. When it passed, he wrote a letter to the editor of the local paper saying that "it is, I believe, impossible to justify the sacrifice of even a portion of our historic individual liberty for a purpose such as this."

He also repudiated that view during his 1971 confirmation.

By the time Republican Richard M. Nixon was elected president, in 1968, Rehnquist had made a good impression on a fellow Arizonan, Richard Kleindienst, who was heading east to join the Justice Department. Kleindienst helped Rehnquist land a job as assistant attorney general for legal counsel, a position in which Rehnquist advised the administration on constitutional law.

In 1969, as anti-war demonstrations raged in the streets, Rehnquist warned a Kiwanis Club in Newark, N.J., of "the danger posed by the new barbarians," adding that "if force or the threat of force is required in order to enforce the law, we must not shirk from its employment."

He was serving at the Justice Department in October 1971, when Nixon selected him to fill a vacancy left by the retirement of Justice John Marshall Harlan. Rehnquist, then 47, was reportedly stunned by the choice, which was indeed somewhat serendipitous: Nixon had turned to him after his judge-picking team, of which Rehnquist was a member, failed to produce a satisfactory alternative.

But Nixon was looking for a cerebral conservative, and Rehnquist did not disappoint.

He soon became known as the "Lone Ranger" because he was so often the sole dissenter on the nine-member court.

Rehnquist opposed the court's short-lived 1972 opinion overturning state death penalty laws. He was one of only two justices to vote against Roe v. Wade in 1973. He opposed affirmative action in higher education. Alone among the justices, Rehnquist said in 1983 that Bob Jones University had a legal right to exclude black students from its campus.

OPPOSED SUBJECTIVITY

Through it all, Rehnquist was motivated by a basic sympathy for law enforcement and the public order it protected, and a certain disdain for the notion that the Supreme Court existed to establish the fairness in society that some might find lacking. That was a job for the legislature, he insisted.

"(F)or the courts to come along and say in addition to that, you know, 'We just don't like what happened here. We think it's, quote, unjust, close quote' is giving them a rather subjective mandate that I think many people ... if they fully understood it, would find troubling," he told an interviewer on Fox News in 2001.

He also held the view that the Warren Court had gone beyond what the framers of the post-Civil War 14th Amendment had intended in guaranteeing "equal protection of the laws" by state governments. Rehnquist felt that, in fact, the amendment was meant to proscribe a narrow range of discriminatory conduct and that only the Supreme Court, not Congress, had the power to say what that conduct would be.

He was particularly offended by what he saw as the excessive use of petitions for habeas corpus by criminal defendants to challenge their state convictions and sentences in federal court. Those constitutional challenges affronted state sovereignty, Rehnquist believed, and excessively delayed executions.

Inside the court, Rehnquist was generally well-liked, despite his disagreements with colleagues about the law.

When President Ronald Reagan named him to replace Warren Burger as chief justice, in 1986, Rehnquist brought a new tone to the job.

He was a stickler for decorum and punctuality in the courtroom and occasionally erupted at wayward attorneys. Yet behind the closed doors of the justices' weekly conferences, Rehnquist was appreciated for his evenhandedness and calm — which justices found a welcome contrast to the imperious Burger.

CUT COURT'S CASE LOAD

Rehnquist believed that the court should reserve its time and effort for cases of national importance that absolutely require its attention; the number of cases decided by the court after briefing and oral argument declined on his watch from 152 in 1986-1987, his first term as chief justice, to 76 in the 2004-2005 term.

With the confirmation of Justice Clarence Thomas in 1991, Rehnquist had the five usually conservative votes he needed to put his views of the law into effect. Habeas corpus was further reined in. Affirmative action was subjected to the same degree of constitutional scrutiny as discrimination against minorities.

The Federalist Five, as Rehnquist, O'Connor, Antonin Scalia, Kennedy and Thomas came to be known, issued a series of rulings that struck down efforts by Congress to subject state governments to laws protecting women against domestic violence, banning guns near school property and prohibiting discrimination against disabled workers.

To critics, this was an effort to roll back the primacy of national government that had been established by the Union victory in the Civil War. To supporters, the court was restoring an appropriate balance of power. But there was no question who the driving force behind the cases was.

"You can't identify anyone who's had more to do with the revival of federalism than Bill Rehnquist," said John C. Jeffries Jr., dean of the University of Virginia Law School. "That means not only limits on federal legislative power, but also that state legislative power ought to be respected."