All deaths of detainees in U.S. military custody are to be reported immediately to criminal investigators under a policy announced by the Pentagon yesterday, following disclosures about lengthy delays in the military's response to prison fatalities, even those ruled homicides.

The policy, according to a two-page memorandum that Defense Secretary Donald H. Rumsfeld signed Wednesday, "reiterates and clarifies" existing rules. But the decision to restate and synthesize those rules reflects the increased scrutiny on detainee deaths that has accompanied revelations about prison abuses in Iraq and Afghanistan.

Under the policy, when a detainee dies, the commander of the detention facility or military unit having custody is required to report the death to Army, Navy or Air Force criminal investigators. Those investigators must in turn contact the Office of the Armed Forces Medical Examiner, which in most cases will perform an autopsy.

The Defense Department also said that the military's regional combatant commanders must notify the secretary, through the chairman of the Joint Chiefs of Staff, of all deaths of prisoners of war and other detainees in military custody.

"With this guidance the department has established a very high standard . . . with regard to the reporting and handling of a death of someone held in custody," the Pentagon said in a statement.

Tardy or lax investigations into deaths in Iraq and Afghanistan have come under criticism this year.

Last month, the Pentagon disclosed that it had opened 30 investigations into 34 deaths at detention facilities in both countries. The investigations make up one-third of the 91 cases of possible abuse and misconduct in both countries that have been investigated since late 2002.

Of 23 death certificates released by the military last month, 20 were signed between May 12 and 21, although some of the deaths had occurred months earlier. Nine of the 23 deaths were homicides, including several that occurred before this year.

One detainee, identified only as Dilawar, died Dec. 10, 2002, at the Bagram Collection Point, the largest U.S. detention facility in Afghanistan. The death was ruled a homicide caused by "blunt force injuries to lower extremities, complicating coronary artery disease," but the certificate was not completed until May 20.

Another detainee, Dilar Dababa, died from a "closed head injury with a cortical brain contusion and subdural hematoma" on June 13, 2003, at an undisclosed location in Iraq. That homicide was not certified until May 14.

A third detainee, Manadel Jamadi, died in Baghdad on Nov. 4, 2003. A pathologist signed off on the homicide, which was attributed to "blunt force injuries complicated by compromised respiration," on May 13.

Pentagon officials have said that the delays in completing the certificates did not necessarily compromise criminal probes because autopsy reports had been completed and passed on to investigators.

Several legal experts said there has been a strong need for clearer reporting procedures since the U.S.-led war began in Afghanistan in 2001.

"It's never too late to do the right thing, but it should have been done sooner than this," said retired Rear Adm. John D. Hutson, who was the Navy's judge advocate general from 1997 to 2000. "Criminal investigators should be the first people brought to the scene, and the ones to make the determination whether or not the death is suspicious," said Hutson, dean of the Franklin Pierce Law Center in Concord, N.H.

Retired Air Force Col. Scott L. Silliman, who teaches law at Duke University, said the policy is largely a response to criticism over the Army's handling of the Abu Ghraib prison abuse. "This announcement is reactive and to some extent to counter the perception that the Army was trying to hide these deaths," he said. "The Army is coming out and proclaiming there will be a procedure to ensure what should already have been the case."

Elizabeth Lutes Hillman, a former Air Force officer who teaches at Rutgers School of Law in Camden, N.J., said better reporting is only a first step. "A list of the dead doesn't constitute an investigation," she said. "With the levels of secrecy and control around military prisons and detention facilities, especially at this time of heightened concern about the disclosure and protection of information, there's not a lot of information about these detainees. . . . Disappearing quietly is much more possible."