Sidestepping the national debate over school vouchers, the Supreme Court yesterday refused to take up a challenge to a Maine law that subsidizes students who attend private high schools but excludes those at religious institutions.

Parents seeking state reimbursement for their children's parochial school tuition challenged the policy as discriminating against religion. But the justices declined the chance to set out national rules about when public money can be used to pay for religious schools, a growing area of controversy as states experiment with programs that give students, particularly poor ones, alternatives to public education.

On a day of varied court business, the justices agreed to hear an appeal brought by independent counsel Kenneth W. Starr, who is trying to revive a tax evasion case against former top Justice Department official Webster L. Hubbell, a friend of President Clinton.

The legal question, to be argued in early 2000, concerns when prosecutors can use documents that an individual surrendered under a grant of limited immunity from prosecution. Hubbell claims the independent counsel violated his immunity deal, and thus his Fifth Amendment right against self-incrimination, when the office used his relinquished financial records as a basis for the tax charges.

The D.C. Circuit appeals court made it difficult for prosecutors to use such materials, and the high court's ruling in United States v. Hubbell could affect a range of federal investigations. As for Hubbell, under an unusual plea agreement his misdemeanor tax charge will be wiped away if Starr loses the case.

Separately, the justices rejected an appeal by Oklahoma City bomber Terry L. Nichols, convicted of conspiracy in the 1995 bombing that killed 168 people. Nichols, sentenced to life in prison, argued that his conviction should be overturned because prosecutors failed to prove that he intended to kill someone. The high court declined his petition in Nichols v. United States without comment or recorded vote. (His partner, Timothy J. McVeigh, was convicted of first-degree murder and sentenced to death in a separate trial.)

The fate of Maine's tuition policy has been closely watched by advocates and opponents of vouchers nationwide. Lower courts wrestling with various school funding programs have issued conflicting opinions on the proper constitutional boundary between church and state, but the high court has shown little inclination to enter the fray. Last week, it declined to review an Arizona program--upheld by the state supreme court--that gives tax credits to people who make donations to religious schools.

In the largely rural state of Maine, parents who live in a school district without a public high school are partially reimbursed if they send their children to a private high school. But the state refuses the subsidy for students who attend religious schools.

Two sets of parents whose children attend Catholic high schools challenged the policy as violating equal protection of the laws and the free exercise of religion. A federal appeals court and the state's highest court separately rejected the challenges, ruling that if the state provided reimbursement for religious schools it would run afoul of the Establishment Clause's requirement for the separation of church and state.

The parents contend that government reimbursement could be considered neutral, rather than an advancement of religion, if the money were provided directly to parents who independently chose the school. They noted that the high court last year declined to hear a challenge to a Milwaukee program that provides vouchers for children who attend all private schools, including religious institutions.

But the Supreme Court, without comment or a recorded vote, rejected appeals in both Maine cases, Bagley v. Raymond School District and Strout v. Allbanese.

In separate religion cases, the justices refused to take up Pennsylvania's appeal of a lower court ruling striking down its state sales tax exemption for Bibles and other religious publications (Pennsylvania v. Newman), and rejected New York state's third attempt to create a special school district for the disabled children of Hasidic Jews in the Kiryas Joel community. Three justices--Sandra Day O'Connor, Antonin Scalia and Clarence Thomas--said the court should have heard the New York case, Pataki v. Grumet.

Finally, the justices refused the appeal of a poor, mentally retarded Georgia prisoner who contended that death row inmates have a right to an appointed lawyer when they raise fundamental constitutional claims in their second round of appeals.

Ignoring unusually impassioned briefs from the NAACP Legal Defense and Educational Fund, the Southern Center for Human Rights and the American Bar Association, the justices in Gibson v. Turpin let stand a Georgia Supreme Court decision that there is no such right to counsel.