Boston — Smile, you're on TV. This advice - or warning - could be given to an increasing number of judges, attorneys, defendants, witnesses, and even jurors, as more court systems allow reporters to use cameras and tape recorders to cover trials.
Thirty-six states have opened some of their courts to television, radio, and photographic coverage. Most of these states have acted on this issue within the past four years. Similar moves are being weighed in five other states.
In addition, a special panel of judges is being formed to explore the possibility of lifting the ban on cameras and sound recorders in federal courtrooms. This group is expected to make recommendations by late next winter to the Judicial Conference of the United States, which governs the operation of the federal court system. The conference is chaired by US Chief Justice Warren E. Burger and comprises the presiding judges of each of the federal appeals courts and district courts in the United States.
It may be several months before the task force holds its first meeting. But those who seek to open federal court trials to newspaper photographers and the electronic media say they have a strong case.
''The news media obviously can do a better job if they are permitted access to the courts,'' maintains Larry Scharff, the Washington attorney representing the Radio-Television News Directors Association, one of 28 organizations petitioning the judicial conference for the rule change.
Backers of the change won't speculate on whether the panel will allow reporters to use cameras and sound recorders in federal courtrooms. But supporters of the petition, filed in March, say they are encouraged by ''steady progress'' in opening up state courts.
The American Bar Association no longer is solidly opposed to camera and sound recorder coverage of trials as it had been for some 45 years. But instead of endorsing such coverage, the organization's new canon, adopted at its annual convention last August, specifies conditions under which a judge may permit taping.
When such coverage is authorized, it must be ''consistent with the right to a fair trial,'' and conducted ''in an unobtrusive manner which will not distract or otherwise adversely affect witnesses or other participants'' or ''interfere with the administration of justice.''
Opponents of the idea are concerned that cameras, microphones, and other picture or sound equipment could give courtrooms a circuslike atmosphere, with trial participants becoming performers. They say jurors and witnesses could be distracted from trial activity, which might work to the disadvantage of the principals in the case.
But boosters of broadcasts from the courtroom say that with proper guidelines there should be no problems. Opening courts to cameras and tape recorders, they contend, is important not only for news coverage, but it also can be used to educate the public about judicial proceedings.
Timothy Dyk, an attorney for CBS, notes that because of the ''revolution in technology of cameras and audio equipment'' in recent years, TV cameras are smaller now and often require no extra light.
''We've not had any complaints about the television or radio coverage of trials since it began here about three years ago,'' says John F. Burke, administrative assistant to the Massachusetts Supreme Judicial Court.
Court officials in other states where the use of cameras and sound recorders is allowed during trials generally report satisfaction with the practice.
William Mann, assistant to the Chief Justice of the Wisconsin Supreme Court, says the system is ''working very well.'' He notes that what began as an experiment in July 1979 has become permanent.
Although only a small fraction of state court trials attract on-the-spot television or radio attention, those of greatest public interest have had extensive daily coverage.
During the past 18 months, provisions for TV, radio, and still-photo coverage have begun or have been extended on a permanent basis in 14 states: Arkansas, Connecticut, Delaware, Iowa, Kansas, Maine, Maryland, Massachusetts, Nebraska, New Mexico, North Carolina, Ohio, Oklahoma, and Oregon.
In Oregon, where still-photo and electronic news media coverage will be restricted to the state's supreme and appellate courts, boosters of the move, like Bill Swing, news director of Portland's KPTV, hope ''this breakthrough'' will open doors in trial courts.
As in most other places where such operations are permitted, state court regulations restrict coverage to one TV camera and one newspaper photographer in fixed, inconspicuous positions in the room. TV and radio stations and newspapers and magazines wishing to cover the proceedings must pool their film and tapes.
In almost all states where TV and radio coverage is allowed, the presiding judge has the final say as to whether it is to be permitted and under what circumstances. In many instances, advance written consent from attorneys and their clients is required.
Many judges exclude cameras or tape recorders when covering trials involving juveniles, sex crimes, and criminal informers, says John Rockwell of the National Center for State Courts. In some courts filming jurors is prohibited, as are bench conferences between opposing attorneys and the judge, he adds.
Besides the 37 states that now have experimental or permanent provisions for TV, radio, and still photo coverage in courts, Louisiana and Nevada have tested the arrangement but have not extended it or made it permanent. In addition, Texas permits sound recording of certain court action but not TV or newspaper photography. Utah allows still photographers, but no TV or radio recording.
Besides those mentioned, only nine states - Hawaii, Illinois, Indiana, Michigan, Mississippi, Missouri, South Carolina, South Dakota, Vermont, and Virginia - prohibit all camera and tape recording in court.