Gena Spero might be legally insane. But if she takes the medication that calms her, she could be in prison for the rest of her life.

The drug dilemma has kept the 25-year-old Spero shuttling between jail, mental institutions and courtrooms since Jan. 10, 1983, the day she allegedly strangled 21-year-old Gina Sindoni, whose nude body was found in a bathtub.After Spero was charged in the slaying, she was diagnosed as a paranoid schizophrenic and placed on anti-psychotic medication. She was found competent to stand trial if she relied on such drugs.

Spero, now a psychiatric patient at Medfield State Hospital, is taking her lawyer's advice to refuse the drugs he calls a "chemical straitjacket" that would give her the equilibrium to face her accusers in court.

Attorney Stephen Colella said that only without the drugs would a jury see her insanity unmasked, accurately reflecting his client's condition the day Sindoni was killed.

Several forensic psychiatrists questioned the ethics of Colella's advice, including Dr. Bernard Katz, who teaches at Boston University and Harvard.

He called the medication Spero would take "mind-restoring, not mind-altering" and said he wondered about the welfare of such patients.

"I feel it's a bad investment on the part of any attorney who recommends this to a patient. . . . Mental illness can be a very painful and troubling and extremely uncomfortable condition for many people," he said.

In a recent interview, Colella said: "They argue that if she's not yelling and screaming, therefore she's cured. . . . If the criminal charges were to go away, she would still be a person who should be committed because she's a danger to herself and society."

Colella backs his legal tactic with a 1981 decision by the state Supreme Judicial Court that a psychiatric patient could refuse medication.

District Attorney Kevin Burke disagrees with Colella, and persists in hoping a judge will find Spero competent to stand trial so he can try her for murder.

But she can't be ordered to take anti-psychotic drugs, and at her annual reviews for mental competency, a judge has continued hospitalization.

"It's in the best interest of justice to have this case tried," Burke said. "Either this is a case of murder, which we allege, or we have a defendant who would be found not guilty by reason of insanity. And the only way that will be resolved is through a trial."

For three years, Spero was incarcerated at the state prison for women at Framingham until a judge ordered her moved to Medfield State Hospital.

Spero was a student at the University of Massachusetts at Amherst when the killing occurred. Sindoni was attending Hampshire College. The two women had been friends about seven months and had shared a house with other women in Northampton for a time.

Spero had a history of mental troubles and checked into psychiatric hospitals on several occasions, Colella said.

Spero's arms are scarred with self-inflicted razor cuts and cigarette burns, Collela said. She hears voices and hallucinates. Since her hospitalization at Medfield, doctors there said she also suffers from temporal lobe epilepsy, Colella said.

Temporal lobe epilepsy, for which Spero takes medication, is a psychologically debilitating illness that can cause sufferers to become suddenly angry or to exhibit other erratic behavior.