EVERYBODY loves a snappy courtroom drama. So why not try the American public education system - which has already been indicted on many counts of aggravated inadequacy - for negligence?On Jan. 6, Public Broadcasting System's MacNeil/Lehrer Productions will present the first segment of "Learning in America: Education on Trial." The innovative three-part documentary was shot in the Denver courtroom where "Perry Mason" is filmed. A real district-court judge presides and first-rate attorneys engage in verbal combat, calling various players in the educational debate to the stand as witnesses. Fatherly Richard Dysart of "L.A. Law" is the host. Each segment asks one essential question: Do we need a national report card? Are our public schools beyond repair? Are we short-changing our schools? At the end of each segment, the viewers are asked to vote by calling an 800 number. The results will be published in USA Today. In effect, you are the jury. "We forged the journalism process with the legal process," says Al Vecchione, president of MacNeil/Lehrer Productions. "And it was the forging of these two processes which is what became so fascinating. The further I got into it, the more I realized how parallel the two are. Good journalism is about fairness, balance, objectivity, and locating truth. This is, in theory, what happens in a court of law. In fact these principles are mandated." The reasoned atmosphere of the courtroom is also familiar enough to TV viewers that even the most complex issues - issues that might seem dull or hard to follow in any other context - become a kind of exciting game. Making a complicated issue interesting for a range of viewers, making the arguments in the "case" easy to follow, presenting both sides of a hot topic fairly, and imparting an enormous amount of information are in themselves educative. The American public is clambering for reform in its educational system, but consensus as to what pattern those reforms should take is far from imminent. Any educative tool which may clarify the issues is welcome at this point. "Education on Trial" helps begin the debate on reform. While the series takes a little while to thaw (the first witness is particularly cold), quite soon the arguments heat up, the attorneys badger witnesses, object to each other's diatribes, and politely scuffle. They are equally matched, and while the exaggerated theatrics of the TV courtroom drama are missing, the two combatants manage to keep each show fairly lively. Neither Christopher Edley Jr. of Harvard Law School nor John E. Coons of the Univers ity of California School of Law defends the public schools from charges of deficiency. In the first segment, "Do We Need a National Report Card?" Mr. Edley argues for a set of national standards to define an adequate modern education backed by national testing to make certain those standards are met. Global economic competition is so fierce and the local and state educational system is so behind other industrialized nations (especially Japan) that it threatens America's future, he states. Mr. Coons argues that if the bureaucracies of state and school districts are failing, then the grander scale of bureaucracy on the national level will only muddle the matter further. He defends the position that parents can make the best choices for their children. Throughout the series, Coons returns to this theme in various ways, promoting further parental involvement in education, and championing choice between public and private education for all parents, regardless of economic status. The second segment gets right down to the real grit when it asks, "Are Our Public Schools Beyond Repair?" Coons argues that school boards are the captives of special interest groups, that they are unresponsive to the needs of parents and students, and that the pervasiveness of poor performance in public school is so systemic that the schools really are beyond repair. Edley argues that the problems in the schools largely reflect the society, that educators are succeeding in some cases even though they are inadequately funded, and that the public-school system is the only just approach to education. The last segment offers the age-old debate over money. Edley demonstrates how much is needed and how desperately; Coons demonstrates how much is wasted on an archaic system. It's a fascinating struggle and viewers may find themselves coming down on decidedly different sides of the argument.