Actor teaches lawyers that 'all the court's a stage'

''There is no right or wrong. There is only truth,'' actor Richard Grusin tells lawyers.

On stage, this maxim means that there is no right or wrong way of portraying a character -- only the one that will have the ring of truth for an audience.

But what relevance does this precept have to the courtroom, where hard facts, not illusions, are supposed to prevail?

Plenty, says Mr. Grusin, who teaches acting methodology to lawyers.

He maintains that acting methods can help attorneys unearth the elements of their personality that will make their courtroom performance more convincing.

Many lawyers seem to agree.

His recent 2 1/2-hour lecture at Harvard University was attended by 50 to 60 attorneys representing some of New England's most prestigious law firms. Because of the success of that seminar, the National Practice Institute, which offers continuing education for professionals, decided to sponsor several more at various universities across the country.

''You are not only the actor in that courtroom,'' Grusin told the lawyers at his Harvard seminar, ''you are the director, the screenwriter, the producer.''

He coaches attorneys on the use of dramatic devices, such as ''builds'' (an approach designed to ''create a sense of suspense in the jury's mind''), upstaging techniques (to distract the jury), and careful use of ''props'' (pieces of evidence) to ''invest them with life.''

''Mistakes can become weapons, very powerful weapons,'' he points out. ''Sometimes, you may want to make a mistake, because (then) the jury will relate to you as a human being. For the same reason, it's wonderful to look scared, because then (the jury will) want you to do well.''

How do such instructions sit with the nation's jurists? Is it ethical for attorneys to use stage techniques to ''create an image in the jury's mind,'' as Grusin suggests? Does such sophisticated methodology cross the line between persuasion and manipulation?

Although they might not subscribe to his theatrical terminology, many legal experts find no fault with Grusin's methods.

''Many lawyers are boring. They have to learn to communicate, to persuade,'' says Richard Gerry, president of the Association of Trial Lawyers of America. ''At least, you want to keep the jury awake.''

And, while he worries about ''an element of showmanship which is suggestive, '' and could become ''hypnotic,'' Daniel Klubock, bar counsel for the Board of Bar Overseers of Massachussetts, basically concurs.

The only disagreement that surfaced during interviews with legal experts was over the question of just how theatrical an attorney should become - not for reasons of ethics, but of effectiveness.

''If a jury gets the idea that you are acting,'' observes former Watergate special prosecutor Leon Jaworski, ''that can be counterproductive. Juries look for facts, and you had better have them.''

Jurors, however, have serious misgivings about Grusin's techniques.

''I would feel as if I were being manipulated,'' says Susan Woo, who recently sat on juries in three criminal trials. Beverly Norton, also a juror at three recent trials, shares her reservations. ''I think it is unethical . . . a method of manipulation.''

Grusin maintains that these techniques are only meant to help attorneys overcome their inhibitions and stilted mannerisms, so that they can ''become human beings,'' and not stuffy lawyers.

But his instructions go beyond personal development.

''Plan out your moves,'' he tells attorneys. ''How much space can you control in that courtroom? That's what it's all about, owning the courtroom.''

''There is no warmth (in a courtroom) at all. The jury is often less educated than you; they aren't allowed to speak; they are totally unfamiliar (with the surroundings). The only one who can make them feel at home is you,'' he says.