WASHINGTON - The Supreme Court made its 1999-2000 term one of history's most consequential by tackling some of America's toughest legal and social issues. Decisions on abortion, school prayer, grandparents' rights, states' rights, police tactics and gay Boy Scouts captured the nation's attention.
''They're not ducking,'' said Mary Cheh, a George Washington University law professor. ''The court showed a certain fearlessness in taking on the cases it did.''
The conservative court, which ended Wednesday the term it began in October, did not always reach conservative conclusions. The justices upheld the famous Miranda warnings police must give criminal suspects before questioning them, banned group prayers at high school football games and struck down a state's ''partial-birth abortion'' law, perhaps dooming similar restrictions in 30 other states.
''It was an amazing term that forces us to give a much more nuanced account of the Rehnquist court,'' said Erwin Chemerinsky, a University of Southern California law professor. ''In some regards it is a very conservative and activist court, but it definitely has its limits.''
The divisive issues were reflected in the court's votes - 20 of the term's 73 signed decisions were reached by 5-4 votes, the highest percentage of one-vote outcomes in more than a decade.
Chief Justice William H. Rehnquist and the court's leading conservatives, Antonin Scalia and Clarence Thomas, were joined by centrists Sandra Day O'Connor and Anthony M. Kennedy in 13 of those 20 cases.
Among them were decisions that let the Boy Scouts ban homosexual troop leaders, prevented rape victims from suing their attackers in federal courts and barred the federal Food and Drug Administration from regulating cigarettes as dangerous drugs.
The loss for rape victims - in which the court struck down a key provision of the federal Violence Against Women Act - was a states' rights victory. Rehnquist wrote that it is up to the states, not Congress, to choose whether to protect women in that way.
''It was a major defeat for Congress, showing that the court has a narrow view of congressional power under the constitutional amendments ratified after the Civil War,'' said Yale law professor Akhil Amar. Those amendments ensure civil rights for all citizens.
O'Connor again loomed as the court's pivotal majority-maker. She cast only four dissenting votes in the 73 cases, compared with nine for Kennedy, 10 for Thomas, 13 for Rehnquist and 14 for Scalia.
The court's four more liberal justices found themselves in dissent more often. John Paul Stevens cast 28 dissenting votes, Ruth Bader Ginsburg, 22; David H. Souter, 21; and Stephen G. Breyer, 18.
O'Connor also limited the conservative thrust of an important church-state decision when she supplied a crucial vote for the majority but wrote separately to voice key differences.
In that case, the court significantly lowered the figurative wall of separation between government and religion by ruling that taxpayer money can be used to supply computers and other instructional materials for religious schools.
Although O'Connor agreed with that result, she refused to join an extraordinarily sweeping Thomas opinion that would have allowed virtually any government subsidy of religious institutions as long as it is not intended to further the religious mission. Rehnquist, Scalia and Kennedy signed on with Thomas - one vote short of a majority.
In one of its most closely watched decisions, the court split 6-3 to limit states' power to help grandparents and others with close ties to children win the right to see them regularly against parents' wishes.
The court stopped short, however, of giving parents absolute veto power over who gets to visit their children and left unanswered many questions state courts face daily in visitation battles.
Other major decisions:
CRIMINAL JUSTICE
-Anonymous tips to police generally do not justify an officer's stopping, frisking and questioning people.
-Police sometimes can pursue, stop and question people who run away at the sight of them.
-Federal judges should not reverse state court rulings in criminal cases unless the rulings are found to be ''unreasonable,'' a standard that makes it far harder for defendants convicted in state courts to get federal court help.
-Presidential friend Webster Hubbell's guilty plea to a misdemeanor tax charge could not stand because he was prosecuted with documents he had been forced to provide under immunity.
-Juries, not judges, must decide whether someone charged with a hate crime was motivated by bias and therefore can be punished more severely.
STATES' RIGHTS
-State employees cannot sue their state or boss in federal court over on-the-job discrimination.
-States cannot be sued by private citizens who accuse them of cheating the federal government.
-Congress can protect motorists' privacy by barring states from selling information on driver licenses.
ELECTIONS AND POLITICAL CAMPAIGNS
-States have sweeping power to impose limits on campaign contributions to political candidates because such restrictions do not violate free-speech rights.
-States violate political parties' freedom of association when they let primary voters choose nominees by voting for any candidate, regardless of party affiliation. The ruling invalidated a ''blanket primary'' law and may threaten open primaries in half the states.
-The federal government cannot reject proposed changes in state and local election systems even if they are discriminatory so long as the changes leave minority voters no worse off. FREE SPEECH
-States have considerable leeway to restrict anti-abortion demonstrations outside health clinics because the right to avoid ''unwanted communication'' can outweigh free-speech rights.
-A federal law that attempted to shield children from sex-oriented cable TV channels violated the First Amendment because it was not the least intrusive means of achieving such a goal.
-State-run schools can subsidize campus groups with money collected from mandatory student activities fees without violating the rights of students who find some of those groups objectionable.
-A dancer's freedom of expression can be restricted by requiring her to wear pasties and a G-string.
BUSINESS
-Federal regulation of auto safety bars state court lawsuits over the lack of air bags in cars built when federal rules did not require them.
-Workers who say their boss illegally discriminated against them can win a lawsuit by showing only circumstantial evidence. No ''smoking gun'' is needed.
