In the world of forensic pathology, there's a morbid truism: Bodies are evidence, and you need a body in order to fully examine a death.
That poses a potentially major challenge for the Puerto Rican government's re-examination of deaths related to Hurricane Maria, which Gov. Ricardo Rosselló ordered Monday after investigations into the official death toll by CNN and other news organizations.
Thousands of people have died since the storm on September 20, according to the Puerto Rican government. Many, if not most, of those bodies have been buried or cremated. That fact will severely limit the US territory's efforts to re-analyze deaths, experts told CNN.
"At this point, the bodies have been buried, and there is no way to do a thorough investigation of each individual case," said Eric Klinenberg, director of the Institute for Public Knowledge at New York University and author of a book about deaths following a Chicago heat wave.
"You'd want to talk with next of kin and neighbors to find out what happened to the person, possibly with doctors as well. But that is very difficult even in the best of times, and right now (many) people still don't have power," he said. "It would require an enormous effort."
Rosselló said Monday that Puerto Rico's Department of Public Safety and the Demographic Registry will re-examine every death that's occurred since the hurricane, regardless of whether the death certificate lists the hurricane as the possible manner of death. The statement from Rosselló's office, however, did not specify exactly how that review would be conducted. A panel of experts will be appointed to review the process, according to the governor.
Neither the governor's office nor the Department of Public Safety agreed to an interview on the details of the review. On Wednesday, a spokeswoman for the governor told CNN that details on how the review would be conducted were still being determined and that the matter would be discussed at upcoming meetings.
The official death toll from Hurricane Maria stands at 64. In reality, it may be many times higher. In November, CNN surveyed half of the funeral homes in Puerto Rico and identified 499 deaths that funeral home directors and staff say were hurricane-related. Later, The New York Times and academics calculated the number of "excess deaths" in 2017 compared with previous years. That analysis led the paper to suggest more than 1,000 people likely died in the storm.
Puerto Rico's governor said Monday that statistical methods will not be used in reassessing the death toll.
"A legal process of certification by a coroner or a doctor is necessary, and every family deserves that the case of their loved ones be looked at independently and thoroughly," he said.
The Bureau of Forensic Sciences, in San Juan, the Puerto Rican capital, is the only laboratory on the island authorized to classify deaths officially as hurricane-related. Pathologists conduct visual assessment and autopsies on some corpses. Documents such as death certificates also can be reviewed, and in some instances family members of the deceased are interviewed.
After Maria, the forensics bureau reviewed many deaths and autopsied bodies before burial or cremation. But CNN also reported that some deaths possibly related to the hurricane were never sent to the forensics office by doctors or other authorities and therefore never were analyzed.
The Puerto Rican government could use death certificates to help re-examine deaths, but those documents alone are not enough to classify deaths as hurricane-related, said Dr. Gregory J. Davis, director of the University of Kentucky's Forensic Pathology Consultation Service.
"Death certificates, unless filled out by an experienced medical examiner/forensic pathologist, are notoriously unreliable," Davis said. Other materials -- including "medical records, police reports, fire/EMS reports, and, though it takes a lot of effort, next-of-kin family statements" -- are needed to make full sense of a death, he said. "It's labor intensive, but if they want the right answers rather than rush answers, they'll do it," Davis said in an email to CNN.
Scientific methods are the most reliable way to understand how and why a person died, said Dr. Brian L. Peterson, president of the National Association of Medical Examiners.
And there always could be some dispute about the circumstances of a death -- especially regarding "indirect" hurricane deaths, or those that resulted from the conditions the storm created rather than the high winds and waters associated with the day of the storm, he said.
"To properly certify a death as other than natural (with respect to manner), we like to have a medicolegal death investigation, an autopsy, and sometimes ancillary studies such as radiology, toxicology, etc.," he said. "More to the point, 'hurricane related' may be more a matter of perception, anyway. Traumatic deaths are easier. Natural deaths are harder to accurately place in the 'hurricane-related' category as death from natural disease may occur at any time."
Exhuming bodies to do those tests would be expensive and unlikely, he said.
It also may not help the research, said Davis, from the University of Kentucky.
"Exhumation is incredibly expensive, involving multiple personnel digging, opening up the vault, bringing up the casket, all with no guarantee that the body won't be quite decomposed or skeletonized, especially in a wet, hot climate such as Puerto Rico's," he said.
Still, Peterson said, "deaths can always be reviewed at any time" with whatever information is available. Davis said it's possible, although not ideal, to review a death without an autopsy.
After CNN's investigation, Puerto Rico added two deaths CNN highlighted to the official toll attributable to Hurricane Maria -- that of Quintín Vidal, who died in a fire started by a lantern he was using because of prolonged power outages, and José Rafael Sánchez Román, whose family said he died of a heart attack or stroke during the storm.
But three additional cases highlighted by the network show how much effort it would take the Puerto Rican government to reassess thousands of deaths that followed the hurricane.
Earlier this week, the Department of Public Safety told CNN those three additional cases do not warrant inclusion on the list of official deaths. Juan B. Robles Díaz committed suicide because of a pre-existing medical condition, not because of the storm, according to a statement sent to CNN by the Department of Public Safety.
In a November interview, however, Robles' son told CNN that his father suffered from night terrors in which he ran into the street screaming about how floodwaters were coming back. He sat by a window watching for the moment water would return to wash him away, Carlos Robles said. He told CNN there was no question his father committed suicide because of the stress of Hurricane Maria and its aftermath.
Yes, he had been diagnosed with cancer, the son said, but that was beside the point.
Puerto Rico did not add his death to the official tally.
In the case of Pilar Guzmán Rios, whose family told CNN she died because a breathing machine she required couldn't run without power, and because the insulin that treated her diabetes could not be properly refrigerated, the case was never reviewed by the forensics office "because the doctor certified the deceased on the death certificate as natural," the department said.
The doctor, Francisco Berio, however, told CNN he made that determination without having seen Guzmán's body, and partly because he wanted her family to be able to bury her more quickly and forensic review would slow that process and prolong grief.
Investigators "tried to interview the son of the deceased, but the attempts were unsuccessful to the point where the relative did not respond to calls," an emailed statement said.
About 15% of cellular sites remain nonfunctional because of the hurricane. It's often difficult to receive calls from the mountainous interior of the island, where Guzmán's family lives.
"The death cannot be attributed to the hurricane," the Department of Public Safety said.
Finally, José A. Molina's son, Luis Alberto Molina, told CNN in November that his father died of a heart attack because of the stress of running a funeral home after Hurricane Maria.
The department said it "investigated the case and requested his medical file." "The gentleman had health conditions such as high blood pressure and cardiovascular disorders. On October 8, 2017, he arrived at the hospital due to a chest pain that he was suffering two days before receiving medical attention. Neither the patient nor the relatives in the interview conducted by the doctors in the hospital attribute his situation to Hurricane Maria. Molina died on October 11, 2017. The death cannot be attributed to the hurricane."
Any death that resulted from the storm or the conditions it created should be counted as part of the official toll, according to Puerto Rican officials. Heart attacks and suicides are included on the official list of deaths that Puerto Rico is attributing to Hurricane Maria. The information matters not only for the accuracy of the count, and the public's understanding of the magnitude of the disaster, but also to families of the deceased. They may be eligible for money from the Federal Emergency Management Agency to cover some funeral expenses.
"Every life is more than a number, and every death must have a name and vital information attached to it, as well as an accurate accounting of the facts related to their passing. That's the law," the governor said in Monday's announcement.
Davis, the University of Kentucky professor and medical doctor, said it's worth the effort to examine cases individually. And it's possible with proper funding.
"It's never too late to try," he said.
CNN's Leyla Santiago contributed to this report.