The head of a commission investigating disclosures that a Florida medical examiner provided executed prisoners' brains for a research project on the criminal mind without permission from the inmates or their families has defended the action, saying it was legal.

"The law says we don't need consent," said Dr. Wallace Graves, head of the Florida Medical Examiners Commission, a regulatory body of state officials that oversees the medical examiner's office and is investigating the incident for possible legal and ethical violations. "If you have a unique population, you're obliged to study it for the benefit of everyone."

Graves' viewpoint was disputed strongly by civil rights lawyers, who say Florida law limits medical examiners doing autopsies to conducting research related to the cause of death.

And biomedical ethics experts say that removal of an organ without permission for medical research not linked to the cause of death violates religious and ethical traditions that the dead do not lose all rights to their bodies. Relatives of executed prisoners agree.

"It increases my feelings of bitterness," said Ann Palmes, whose son, Timothy, was electrocuted in November for stabbing to death a Jacksonville store owner. "It all hinges on permission. They did it without permission. So far I don't believe we belong body and soul to the state . . . . Death was a punishment for what they claim he did. To go beyond that and take something else from him besides his life is a form of robbery."

"This research is totally out of step with the ethics of research for the past two decades. It's going backwards, not forwards," said Arthur Caplan of New York's Hastings Center, a biomedical-ethics think tank. "I was shocked to hear that family members were in no way contacted about this."

"The basic thing it suggests is a willingness to take advantage of vulnerable people who may not be in a position to control their own destiny," said James Childress, professor of religious studies at the University of Virginia in Charlottesville.

The unapproved use of brain tissue from executed prisoners in Florida, which was reported last week in The Washington Post, appears to be confined to Florida, according to interviews with prison wardens and medical examiners in other states.

In Florida, Graves' commission expects to assess its findings next week. In addition, the office of the state's attorney will review the findings for possible legal violations.

In an interview this week, Graves said the actions of the medical examiner, Dr. William Hamilton, were ethically, as well as legally, defensible. "It might be unethical and immoral if he didn't" pursue the research, Graves said, because the research is "in the public interest." But he said he intended to form an "ethical advisory council" of clergy members, researchers and journalists "to advise us on problems like this."

Hamilton removed portions of the brains of executed prisoners during the past two years and then provided the tissue in February to University of Florida researcher Christiana Leonard, according to a spokesman from the University of Florida. Twelve men have been executed in Florida since November 1983.

Leonard and Hamilton were trying to determine whether a connection existed between head trauma suffered during childhood and criminal behavior.

They did not seek permission for use of the brain tissue from the prisoners or their families, according to a public defender who represented the prisoners as well as a member of Hamilton's office staff.

A University of Florida vice president also defended the research. David R. Challoner, vice president for health affairs, said that Florida law grants the medical examiner the authority to perform "whatever autopsies or laboratory examinations he deems necessary in the public interest."

But Susan Cary, a public defender who represented the prisoners, said the law is more specific and does not refer broadly to the public interest but to determining the cause of death or injury.

In addition, Cary said, organ-donor law in Florida requires permission for experimentation on organs.