Yesterday's court ruling that hospitalized mental patients have a constitutional right to refuse treatment will not affect current practices in Harvard-operated mental health institutions, James T. Hilliard, special counsel to the Massachusetts Mental Health Center, said yesterday.

"It has never really been a major problem. The Massachusetts Mental Health Center hasn't forced treatment on patients in the past," Hilliard said.

Prominent teaching institutions have given hospitalized patients this right since the suit that led to the recent decision was filed in April, 1975, Thomas G. Gutheil, acting director of the adult in-patient services at the Massachusetts Mental Health Center and Assistant Professor of Psychiatry, said yesterday.

U.S. District Court Judge Joseph L. Tauro's decision says that "the state's duty is to make treatment available; it has no duty to impose treatment."

"It is going to be a very difficult decision to deal with," William J. Curran, Lee Professor of Legal Medicine, said yesterday. "It's a good basic legal principle to be able to refuse treatment. But this is not always in the best interest of the patient. They are making rulings that seem to be helping the rights of people, but don't seem to be helping their welfare," he added.

Curran said the decision overreacts to the problem of doctors over-prescribing drugs to quiet down patients, and could cause an overreaction in the opposite direction, with patients refusing clearly helpful medication.

"This represents a fairly predictable extension of legal principles," Gutheil said. Since the medication prescribed alters thinking, it interferes with the patients's legal right to freedom of speech, the court reasoned in its decision.