D.C. Chief Medical Examiner Jonathan L. Arden said yesterday that two of his medically trained staff members "made an honest mistake," when they reported feeling a pulse on a District woman who was believed to be dead and had been placed in a refrigerator at the morgue.

Arden said there was the "perception" that the staff members -- a physician and physician's assistant -- felt a pulse. But, he added, what they were feeling was likely their own pulse in their fingers.

The Washington Post reported yesterday that Deborah Wilson, 49, was found Friday in her Northwest Washington apartment and sent to the morgue and that later the two staff members detected a pulse, according to a written report.

"There are times when human beings make mistakes," Arden said yesterday at a news conference outside D.C. fire department headquarters in Northwest Washington. "They understand now there could not have been a pulse at the time." He maintains that the woman was dead when she was taken from her apartment.

Medical experts said yesterday that the mistakes described by Arden were in the realm of possibility, even among highly trained medical professionals. One doctor who asked not to be named said: "You can perceive your own pulse as their pulse. You can be mistaken about it."

But Cyril Wecht, the coroner in Allegheny County, Pa., and past president of the American Academy of Forensic Sciences, said he had never heard of more than one person making the same pulse-taking mistake. "It's a rarity times a rarity," Wecht said.

A report written and signed Friday by Mary Beth Petrasek, the physician's assistant, said that both she and a doctor felt a pulse on Wilson. A male employee in Arden's office then called 911 and told the dispatcher that the woman had a pulse, according to the 911 tape released yesterday by the fire department.

Arden refused to allow the physician and physician's assistant to be interviewed yesterday.

"They're not available," Arden said after the news conference, which the two staff members did not attend.

He criticized several staff members in a closed-door meeting yesterday for allegedly leaking information about the incident, sources familiar with the matter said.

The chain of events began Friday when the manager at Wilson's apartment building called 911 because Wilson had been found on the floor by workers in the building.

Fernando Daniels III, medical director for D.C. Fire and Emergency Medical Services, said "two very seasoned paramedics" were dispatched to Wilson's apartment and "found no signs of life." Fire department officials declined to release the paramedics' report, saying it was not a public document.

The paramedics notified the D.C. medical examiner's office. Two and a half hours after paramedics were dispatched, mortuary technicians from Arden's office arrived to retrieve Wilson's body. Petrasek, the investigator on the case, failed to show up because she was "overwhelmed with cases," Arden said. It is standard procedure for a physician or physician's assistant from the medical examiner's office to be at the scene to pronounce a person dead.

The technicians placed Wilson in a body bag, took her to the morgue and put her in a refrigerator. Petrasek, who was called to pronounce Wilson dead, then found a pulse.

"This investigator thought there may be a slight pulse," Petrasek wrote in her report. She called Constance DiAngelo, a physician, to verify it, "and she, too, felt a faint pulse," Petrasek wrote. Wilson was then removed from refrigeration and an employee called 911.

"We need an ambulance here for possibly a decedent who's not actually deceased," the employee told the dispatcher.

"He's not deceased. . . . Is he breathing?" the dispatcher asked.

"She. It's a she," he said. "No. . . . We have one of our pathologists and one of our medical investigators are attending."

"Does she have a heartbeat?" the dispatcher asked.

"They believe so, yes. They feel a pulse."

Paramedics arrived and placed Wilson on a cardiac monitor, but she showed no heart activity, Arden said.

"She continued to have clear-cut signs she was dead," he said. "She was in rigor mortis. It is an unequivocal sign of death."

Chief Medical Examiner Arden, with Fernando Daniels III of D.C. Fire and Emergency Medical Services behind him, said at a news conference, "There are times when human beings make mistakes."Chief Medical Examiner Jonathan L. Arden said the staff members "understand now there could not have been a pulse" when the woman was checked at the morgue.