ACELEBRATED criminal case, as writers from Damon Runyon to Rebecca West long ago demonstrated, makes an absorbing tale even after the verdict is known. Myron Farber's book, a minor gem of that genre, tells the curious story of Dr. Mario Jascalevich, a New Jersey surgeon who was tried in 1978 for three (originally five, in the indictment) mysterious hospital deaths 12 years earlier in the Riverdell Hospital, Oradell, New Jersey.

The "Dr. X" case is itself fascinating enough. But interwoven with this study in medical detection is the story of Farber himself, a New York Times reporter whose diligent reporting helped jar the case, after a decade, from the files of the Bergen County prosecutor's office.

Farber's involvement cost him several weeks in jail and his newspaper upwards of $200,000 in contempt fines. Farber, subpoenaed by Dr. Jascalevich's defense, refused on First Amendment grounds to turn over his investigative notes and documents. The Farber case thus became one of the more celebrated of hundreds, major and minor, in which courts during the past decade sought to use reporters as arms of prosecution, investigation or (in this case) defense.

Suspicion was not long gathering about the Riverdell case when some 15 patients died there unaccountably in 1966. None of the deaths could be satisfactorily explained by conventional pathology. One marvels, indeed, at the pseudo-medical language that sometimes passed muster in coroner's reports. For instance, the sudden death of 4-year-old Nancy Savino after uncomplicated abdominal surgery was ascribed after autopsy "to an unexplained physiologic catastrophe."

Suspicion soon focused on Riverdell's suave, Argentine-born chief surgeon, Dr. Mario Jascalevich. Fellow surgeons discovered more than a dozen curare vials and several syringes in the doctor's hospital locker. They notified authorities, who investigated but ultimately decided not to seek indictment. Dr. Jascalevich contended then, and at his eventual trial 12 years later, that he had used curare (which paralyzes the respiratory system) in laboratory experiments on dogs at nearby Seton Hall medical school. So he had, some years earlier.

At the long trial, running from February through mid-October 1978, the prosecution presented testimony based on sophisticated lab analysis of the tissues of five of the victims -- their bodies had been exhumed -- that traces of curare were present and probably caused death.

An expert swashbuckling defense, mounted by one of New Jersey's top criminal lawyers and his own battery of pathology experts, rested primarily on the contention that curare traces could not last 10 years and, in any case, would have been broken down by embalming fluids. This, apparently, sufficed to raise a "reasonable doubt" and win a surprisingly quick acquittal from the jury. Nonetheless, Dr. Jascalevich was soon deprived of his medical license on other grounds by New Jersey authorities. He eventually returned to Argentina -- formally exculpated but still under a cloud.

The irony of the tale is that the dramatic mid-trial subpoena to Myron Farber came to little, except for the cost to Farber of doing time in jail for his principles. The trial wound to its conclusion, the doctor was acquitted, without benefit of Farber's notes. Jurors later said that these materials would not have affected the outcome. A New Jersey Supreme Court decision in Farber's case, though it went against him 5-2, reinforced the conditional immunity of reporters to dragnet subpoenas and led to a rewrite of New Jersey's "shield law" which had been disregarded on constitutional grounds in his case.

It is uncertain, even now, what this fascinating double case proved about medical murder, the administration of criminal law, or the role of the press -- unless it was that great newspapers, and reporters of Farber's caliber, often bring to bear greater investigative resources and skills than harried prosecutors. If so, the temptation to use subpoena powers indiscriminately to exploit superior journalistic investigation will grow -- at least so long as the U.S. Supreme Court tolerates the practice. The court's 1972 ruling in Branzburg v. Hayes, minus the cautionary reservations of Justice Powell, were interpreted in New Jersey as sustaining the "blanket" subpoena against Farber.

Incidentally, neither Farber nor The Times contended that a reporter is exempt, in criminal processes, from the law's traditional expectation of every man's evidence; only that reporters should be protected against unfocused "fishing expeditions." Dr. Jascalevich's defense lawyer didn't specify, and probably didn't know, what he was looking for in Farber's files. In fact, there is evidence that Farber was called to testify, and his notes subpoenaed, to play on jury sympathies. The defense attempted to portray Farber -- falsely -- as party to a "conspiracy" against Dr. Jascalevich by the press and Bergen County prosecutors. Given the cloudy state of the law, press subpoenas are a field ripe for abuse.

The only redeeming result -- apart from enriching this bizarre tale of suspected medical murder with the teller's personal legal ordeal -- is that Gov. Brendan Byrne recently "pardoned" Farber for contempt and made partial restitution of his fine to The Times. It was a handsome gesture. But really, who needed pardoning? Surely it was the state of New Jersey for its dubious treatment of a diligent and independent reporter, seeking to do his duty.