The Supreme Court yesterday took a tentative but significant first step toward defining the right of court access it conferred upon detainees at the U.S. naval base in Guantanamo Bay, Cuba, issuing an order seeking a federal appeals court's opinion on where a detainee's case should be heard.

The court told the San Francisco-based U.S. Court of Appeals for the 9th Circuit to reconsider a ruling last fall in which it permitted a Guantanamo detainee to contest his detention in federal court in California.

The justices asked the 9th Circuit court to redo that ruling in light of their decision in the case of Jose Padilla, a U.S. citizen being held as an "enemy combatant." In that ruling, which, like the Guantanamo decision, was issued Monday, the court said Padilla should have filed his request for freedom in South Carolina, where his immediate jailer, the commander of a naval brig, is located, rather than in New York.

It appears, then, that the high court wants the 9th Circuit either to explain why it believes the Padilla ruling does not prevent the case of a Guantanamo detainee from being heard more than 3,000 miles away -- in California -- or to suggest a more appropriate locale.

The court's order shows that, while the justices may have decreed a broad right of court access for the detainees, the prisoners' fate hinges on myriad procedural considerations, especially such issues as exactly whom the prisoners may sue for their freedom and which judge or judges will ultimately rule on their pleas.

The Supreme Court wants to prevent detainees from "forum-shopping" among the dozens of federal district courts around the country.

At the same time, it is not clear which courts are entitled to rule on cases emanating from Guantanamo, which is formally part of Cuba.

In the Guantanamo case it decided, the Supreme Court allowed a group of British, Australian and Kuwaiti detainees to file for a writ of habeas corpus in the federal district court in Washington, D.C., reasoning that the government had not questioned its jurisdiction over President Bush and Defense Secretary Donald H. Rumsfeld, as well as four military officers whom the detainees named as their custodians.

But in saying that Padilla should have directed his petition to the Navy officer in charge of the brig where he is being held, rather than to Rumsfeld, the court seemed also to prefer a location for an initial hearing as close as possible to where the prisoner is being held.

Falen Gherebi, the subject of the 9th Circuit case, is described by the government as a foreign national whom U.S. forces seized during fighting in Afghanistan. Through his brother, Belaid Gherebi, he initially filed for habeas corpus before a federal judge in central California, naming Bush and Rumsfeld as his custodians.

The case is Bush v. Gherebi, No. 03-1245.