The D.C. City Council gave preliminary approval yesterday to a "death with dignity" bill that would permit adults to declare in advance that they would rather be allowed to die than be kept alive in a hopelessly comatose or terminally ill condition.

The law would be the toughest of its kind in the country, according to one authority, because it would impose fines and legal sanctions against any doctor refusing to comply with the patient's wishes.

Violations would carry a maximum penalty of a $5,000 fine and suspension or revocation of a physician's license under the city's Healing Arts Practices Act.

"If the new D.C. ordinance specifically says that, then it certainly has placed some teeth into the legislation which previously no other state has done," said Paul Armstrong, a New York lawyer. Armstrong represents the family of Karen Ann Quinlan, a comatose woman whose plight aroused a national legal and moral debate over when heroic -- but apparently futile -- medical measures should be withdrawn.

Ten states (not including Maryland or Virginia) have adopted similar laws enabling residents to file affidavits with their doctors, that reject life-sustaining treatment -- such as continued use of a respirator -- in the event that they become fatally ill or lapse into a hopeless coma.

The D.C. council bill would allow hospitals to discontinue life-sustaining treatment for any patient, 18 years or older, who signs one of the affidavits, provided that at least two doctors conclude that the patient is in a "terminal condition" with no chance for recovery.

Patients could revoke their affidavits at any time. And safeguards were written into the legislation to protect elderly or mentally incompetent people from being forced or tricked into signing "death with dignity" affidavits by relatives who might grow tired of caring for them or want to get a share of an inheritance.

"The bill specifically prohibits implementation of the document against the will of the patient," said Polly Shackleton (D-Ward 3), chairman of the council's Committee on Human Services and chief sponsor of the bill.

"If the person is alert and communicative at the time of diagnosis of the terminal condition, then the doctor must tell the person about his or her condition," she said. "This gives the person an opportunity to reevaluate the decision."

Shackleton said the bill does not provide a license for mercy killings.

The bill also would protect doctors who follow the patient's instructions against civil malpractice suits stemming from the patient's death.

The council yesterday also gave preliminary approval to a related bill introduced by Shackleton that codifies and expands the legal definition of death to include "brain death," which the measure defines as the irreversible cessation of all functions of the brain and the brain stem.

Twenty-seven states, including Virginia and Maryland, have adopted some type of brain-death standard, according to Shackleton.

Until now, legal and medical authorities here have had no statute to guide them in deciding life-and-death issues. They relied instead on the common-law definition of death, which is the total failure of an individual's heart and lungs.

In August 1980, the city sought a court ruling to declare a comatose, 9-year-old Washington boy brain dead and to authorize doctors at D.C. General Hospital to discontinue the life-support systems that had kept him alive, over the objection of his parents.

The youth, Yusef Camp, was stricken the previous May after having ingested an unknown quantity of drugs. A D.C. Superior Court judge dismissed the court case on Sept. 18, 1980, two days after the boy died of cardiac arrest.

Shackleton said yesterday that Camp probably would have been ruled dead if her proposed legislation had been in effect at the time.

Shackleton's two bills have won widespread support from members of the medical and legal profression here, but drew fire from The Most Rev. James A. Hickey, Archbishop of Washington.

In a Sept. 8 letter to Shackleton, Hickey warned that her bills "could contribute to a declining respect for human life, especially the life of the feeble, sick and handicapped."

He said the "death with dignity" bill might lead to abuses and practices "which would work against the real interest of the terminally ill, their families and the physicians which serve them."

Echoing that concern, council member H.R. Crawford (D-Ward 7) cast the only vote against the proposal yesterday. The council will take final action on the measures at its next meeting, Oct. 13.

"There are some things we should leave alone," Crawford said after yesterday's meeting. The possibility of abuse is great . . . .

Council member David A. Clarke (D-Ward 1) formally objected to Shackleton's so-called Uniform Determination of Death Act, arguing that it failed to meet the strongest burden of proof in determining when life ends.

Noting that a patient's circulatory system often continues to function after being disconnected from a life-support system, Clarke added: "Serious consideration needs to be given to the legal as well as other ramifications of conduct involving a warm body with a beating heart which is legally dead."