Reasonable doubts

Trial by jury has many things in its favor, not least its guaranteed status in federal and state constitutions. It is, of course, more cumbersome than trial by judge: a judge sitting alone can usually conclude litigation in two-thirds the time that a jury trial takes. And, some people think, jurors are more prone to emotional excesses than judges - as though beneath the robe sits a heart as unemotional as the courtroom marble and as level in its contemplation as the wooden bench of justice.

To the system's enthusiasts, however, this is mere lint on the toga of justice. Juries, they say, are good for justice and for society because they utilize the common sense and native wisdom of 12 heads (actually, in some courts , only six heads - but still considerably more than one). Also, a jury comes from the whole community, so it directly represents the people in the resolution of civil disputes and in the disposition of criminal offenses.

With the computer revolution we are now able to place the entire adult population on the jury roll. Several states have scrapped the old apparatus of ''jury duty,'' which required citizens to devote a whole month or more to this service - and to spend most of their conscriptive time waiting in dank chambers called, with sardonic metaphor, jury pools.

The new dispensation calls in a fresh batch of prospects daily; if a person does not ''make'' a jury that day, her or his obligation ends until the next time the computer beckons, a pause statistically likely to last about 20 years. Even a juror who wins a seat in the box need serve no more than that one trial.

This constant turnover of citizen-arbitrators means not only that the burden of jury service rests on many more shoulders, but that a much broader section of the public than ever before gets hands-on experience in the administration of justice. More important, an ever-increasing army of citizens will now learn something about the law.

The juror acquires knowledge in two ways. First, by observation of the courtroom activities and procedures. Second, by direct education in legal principles.

It is this last which furnishes the great paradox of the jury system. A group of ordinary people, interested and sincere, but nonetheless ignorant of legal matters and untrained in legal concepts, are expected to acquire an instant familiarity with concepts which defy ready analysis (or, frequently, any analysis). They are aided only by a brief lecture delivered by a lecturer who is almost invariably as inexperienced in teaching as his listeners are in hearing cases.

From the lecturer's standpoint, the paradox is even more acute: the test of his teaching is not the thoroughness with which his students learn their lesson, but rather the degree to which his Board of Education (the appellate courts) find his lecture to make good reading.

In short, a judge's charge is ''good'' if a group of higher judges believe that it has correctly excerpted and quoted the upper court's prior opinions. Whether this language, originally conceived by legal minds for consumption by other legal minds, has in fact enlightened its ostensible consumers, the jurors, is a question that only an impolite trial judge would dare to ask.

This exaltation of visual perfection over auditory comprehension leads to predictable verbal caution. Trial judges, like lawyers, tend to dislike innovation and to accept authority; like people generally, they also tend to abhor criticism, particularly the type of explicit public criticism embodied in a higher court's written opinion.

The result, naturally, is an almost irresistible urge to ''crib'' (this is, after all, quasi academia) from appropriate appellate decisions, and then to read the script to the jury. This ensures only the inclusion of every vital word; it neither guarantees nor encourages juror understanding.

Consider, for example, one everyday judicial experience. As most people know, proof beyond a reasonable doubt is what the prosecution has to establish to convict the defendant. Most judges, however, have great difficulty explaining just what the phrase means; and most jurors, indeed, most lawyers, have even greater difficulty understanding the explanations.

Over 130 years ago, one appellate court defined ''proof beyond a reasonable doubt'' as ''proof to a moral certainty,'' proof that leaves the jury with a clear and settled conviction of guilt, but not proof to a mathematical certainty nor proof beyond all possibility of innocence.

Massachusetts judges have been using the formula ever since. Indeed when one of them strays, the appellate court is likely to deplore this departure from the ''time-tested'' language. Use of illustrative examples is also forbidden, as ''trivializing'' the jurors' task.

So the trial judge goes back to the old text, secure that whatever the jury's confusion, the higher court will approve.

Still, things could be worse. One Midwestern federal appellate court has decided to abandon formal jury education altogether. It has officially instructed trial judges not to explain the meaning of ''proof beyond a reasonable doubt,'' but just to tell the jurors that the term is self-defining. Perhaps that really is the best solution. When you say nothing, you never have to eat your own words.