WASHINGTON — The Supreme Court struggled today with how far states can go in punishing their most incorrigible prison inmates.

A lawyer for Pennsylvania asked the justices to allow the state's prison officials to deny troublesome inmates access to secular newspapers and magazines in hopes of making them behave.

Chief Justice John Roberts repeatedly pressed a lawyer for the inmates to say what options are left for prison officials who have already taken away most of a prisoner's privileges.

"You are saying they just have to grin and bear it?" Roberts asked.

Justice David Souter jumped in, suggesting that the inmates' lawyer may have been arguing that the prison officials' policy could go too far and become "cruel and unusual punishment."

But the lawyer, Jere Krakoff, said that was not his argument. "There comes a time when you take away so much," he said, "that, yes, you may have to give up. You may have to keep them in segregation."

Justice Anthony M. Kennedy said Krakoff's argument made little sense. He said the state should have the option of trying to change inmates' behavior and not "forgetting about them altogether."

As states have gotten tougher on crime, prisons have cracked down on disruptive inmates by creating high-security segregation units with rules designed to cut off contact with the outside world.

In Pennsylvania, prison officials want to put their most incorrigible inmates in solitary confinement and keep them not only from reading secular newspapers and magazines, but also possessing personal photographs, for months and sometimes years.

Lawyers for the state were asking the justices today to reject a claim by inmate advocates who say access to reading material and photos cannot be used as an incentive for the state's most troublesome inmates to behave themselves. The Court is hearing oral arguments in the case, Beard v. Banks, 04-1739.

The key question is whether prison officials can transform constitutionally protected rights, such as freedom of speech, into privileges that can be taken away unless inmates do as they are told.

The case's outcome could affect prison operations nationwide if the justices require state officials to prove that their policies serve legitimate security and rehabilitative interests inside prison walls.

The Bush administration is siding with Pennsylvania, saying the state's policy deserves deference by the courts because it involves maintaining order in prisons.

"It is a matter of common sense that withholding desirable inmate privileges — as a sanction for misbehavior — may deter prisoner misconduct and induce behavioral reform," Solicitor General Paul Clement told the justices in a filing.

But religious and civil liberties groups say fundamental rights are not mere privileges that can be granted or revoked at the whim of a prison official.

Lawyers for the Becket Fund for Religious Liberty worry that prison officials won't stop with newspapers but "declare open season on all constitutional rights" by one day possibly barring inmate access to the Bible.

Pennsylvania prison officials allowed the 40 inmates held in the high-security disciplinary unit to have access to religious materials, two paperback books of general interest, their legal documents and letters from family. But newspapers, magazines and personal photographs were banned.

"Although Pennsylvania exempts religious materials from its policy today, it may not do so tomorrow if it decides that withholding access to religious texts would enhance its leverage over prisoners," the Becket Fund lawyers wrote in a friend-of-the-court filing.

The case also is significant because new Justice Samuel Alito won't participate in the arguments. Alito wrote the dissenting opinion, siding with Pennsylvania prison officials, in the case as a judge on the Philadelphia-based 3rd U.S. Circuit Court of Appeals.

In October 2001, Ronald Banks filed a civil rights lawsuit on behalf of himself and other inmates in the disciplinary unit, then located in Pittsburgh, after prison officials barred him from receiving his subscription to the Christian Science Monitor, a newspaper specializing in foreign-affairs coverage.

The appellate court's majority sided with Banks, ruling that prison officials had failed to show the policy had any effect on behavior or offer proof that inmates had misused newspapers and magazines to start fires or throw human feces at guards.