ASHINGTON, March 1 — The Supreme Court agreed Monday to hear a challenge to a California prison system policy that segregates inmates by race during their first 60 days of incarceration.

The state has defended the policy, and a federal appeals court has upheld it, as a sensible way to minimize interracial violence at the reception centers where inmates are housed while being screened for long-term placement. One purpose of the screening is to assess a new inmate's potential for violence.

During this 60-day period, inmates are assigned to two-person cells based on whether they are black, white, Asian or "other." Within those categories, the authorities also separate some by national or geographic origin. For example, Japanese and Chinese inmates are not housed together, neither are Laotians and Vietnamese, or Hispanics from Northern and Southern California.

The segregation policy is also used for the first 60 days after an inmate is transferred from one prison to another. In all instances, however, areas of the prison other than the actual cells — the yard, dining hall and work and recreation areas — are not segregated.

The policy has been in effect for more than 25 years. Garrison S. Johnson, a black inmate convicted of murder, challenged it in 1997 by filing a federal lawsuit that he drafted himself. The lower federal courts dismissed the suit while permitting him to amend it with a lawyer's help. Proskauer Rose, a New York law firm with an office in Los Angeles, has been handling the case without charge for the past three years.

In the amended lawsuit, both the Federal District Court in Los Angeles and the United States Court of Appeals for the Ninth Circuit, in San Francisco, upheld the policy. In its ruling in February 2003, the Ninth Circuit said there was "clearly a common-sense connection" between using race for the initial assignment and reducing racial violence in the prison system.

"The housing policy does not provide any advantage or disadvantage to any particular race, and the objective, reducing violence among the inmates and against the staff, has nothing to do with race, but rather with inmate and staff safety," Judge Diarmuid F. O'Scannlain wrote for a three-judge panel of the appeals court.

In the Supreme Court appeal, Johnson v. Gomez, No. 03-636, Mr. Johnson's lawyers argue that the Ninth Circuit applied the wrong legal standard, and that a government policy that makes distinctions on the basis of race has to meet a more searching test than that of common sense or reasonableness. All such policies are presumptively unconstitutional, they said.

"The decision below undermines a national imperative to eliminate racial discrimination," the appeal argues. It adds that though segregating inmates by race might be justified in response to an "extraordinary circumstance involving prison security," it should not be a routine part of administering a prison system with 100,000 inmates.

A Supreme Court decision in 1968, Lee v. Washington, prohibited segregation in the Alabama prison system. Though Mr. Johnson's lawyers invoked that precedent, the Ninth Circuit disregarded it on the ground that the court in 1968 was addressing a policy that permanently segregated the prison population into whites-only and blacks-only cellblocks. The California policy, by contrast, imposes only short-term segregation and "is limited to the dangers it seeks to alleviate," the appeals court said.

Rather than the "strict scrutiny" usually applied in race discrimination cases, the Ninth Circuit applied a more relaxed standard of review derived from a prison regulation case the Supreme Court decided in 1987. The decision in that case, Turner v. Safley, said that courts should generally uphold prison regulations that are "reasonably related to a legitimate penological interest." The connection between the regulation and the administrators' goal in issuing it must be a valid and rational one, the court said in that case.

In a separate development Monday, the court declined to act on the Sierra Club's motion to disqualify Justice Antonin Scalia from taking part in a case challenging Vice President Dick Cheney's refusal to disclose information about his energy task force. The justice and the vice president took a hunting trip together in January, after the Supreme Court had accepted the case.

In a brief order today, the court said that "in accordance with its historic practice, the court refers the motion to recuse in this case to Justice Scalia." In other words, the court will not tell Justice Scalia what to do, and he remains free to make up his own mind on whether to participate in the case, Cheney v. United States District Court, No. 03-475.