"The jury, passing on a prisoner's life, may in the sworn twelve have a thief or two guiltier than him they try." -- William Shakespeare, "Measure for Measure," Act II, Sc. 1

"Do not leave personal property unattended in the jury lounge," a monotone voice blares over a loudspeaker. "This is a courthouse. It is guaranteed to be stolen.

"Do not eat, smoke or drink in the jury lounge or courtrooms.

"Do not talk with other jurors about a case on which you are sitting until the trial ends and you deliberate to reach a verdict."

The do's and don'ts of jury duty are easy to forget. Waiting four hours the first morning in the District's institutional-green jury lounge, a semi-formal bus station that routes jurors from case to case, can make you forget your own name. No problem: For the next two weeks, your assigned juror number is more important.

A rote recitation of rules, a slim handbook and the uncertainty and anticipation that pervade the jurors' lounge is the only introduction to jury duty for most of the several hundred District residents selected randomly each week to serve in an ancient and honored legal tradition -- trial by peers. In its modern context, serving as a juror is considered the gravest of civic obligations. But for the average citizen too busy and generally reluctant to judge his fellow man, the jurors' summons that arrives unexpectedly one day in the mailbox often represents an intimidating intrusion of privacy and routine.

"I don't wanna be on no jury," grumbled a weathered man in his fifties, an employe of the Bureau of Engraving -- one of 12 jurors and three alternates seated around the boardroom table in a small jury enclave adjacent to D.C. Superior Court Judge Robert Scott's Courtroom 35. The complaint was an ice breaker for 15 of us with no more in common than the trial and our discomfort. It drew nodding agreement.

Chosen from a pool of 50 jurors the previous afternoon, we waited to file into the jury box to hear the attorneys' opening statements in the trial of a man charged with three counts of armed robbery.

"I'd rather be working," the same juror groaned. "I'd rather be sleeping. All I know is I don't wanna be doing this."

Another juror, a retired English teacher from Cardozo High, stopped him short. "You could be worse off," she scolded. "You could be on the other side of the fence."

The image of the young, sullen man in a green pullover sweater, seated next to the defense attorney the day before during jury selection, was haunting. No one wanted to trade places with him. No one would complain again about serving as a juror during the four-day trial. Talk turned impersonal. "I fixed a leak in the brake line of my Plymouth last week," said Juror No. 12.

No wonder some social scientists and psychologists make a living studying juries. They're a laboratory of human interaction under an artificial set of rules:

* Confine a handful of strangers together for hours, possibly days.

* Restrict how they act and what they wear.

* Assign a formidable task, a tormenting exercise in impartiality with possibly dire consequences for someone else.

* Make that task -- the only thing they have in common at first -- the only topic not to be discussed until final deliberations.

The soul-searching pressure that builds behind the closed door of the jury room fascinates psychologists, playwrights and the press.

It consumes jurors.

Away from the courthouse, they'll talk obsessively to friends and spouses about jury duty. At the courthouse, those who've served on a trial together develop a quiet camaraderie. It emerges mostly after the verdict has been decided, after the prospect of heated deliberation has passed. They'll subtly seek out each other when new jury panels are called. They'll look at each other during a jury selection and shrug as if to say, "Here we go again."

Sometimes they'll move their leatherette chairs together in the lounge and talk about other things. But conversation eventually comes around to the case. Their experiment in justice.

Yet when jurors have completed their duty after two weeks, relieved that it's over, they'll rarely know each other's names. Jurors seldom introduce themselves to each other. It has something to do with the climate of the courtroom. The criminal presence.

Juror No. 12 talked more about automobiles -- a lengthy dissertation on plastic versus metal timing chains. A few of us listened. Some read paperback Gothics that now seemed minimized by the real-life drama outside the door. The white-haired Judge Scott, a portrait of judicial wisdom, opened the door to see if all 15 had arrived.

"Can we smoke in here?" a grandmotherly Juror No. 8 asked him. He raised his hand holding a cigarette to answer. Where you can and can't smoke in the courthouse was the second-most popular subject the first day in the jury room. Lunch at the Marriott Cafeteria at the courthouse's bottom floor came in third.

By Day 2, the jurors had accepted their mutual situation. We arrived on time, but the trial didn't. More waiting. While Judge Scott ran an efficient courtroom, the wheels of justice were stuck in low gear. They grind slowly, says the truism. Delays and recesses and debates over legal technicalities continually dumped us back into the tiny jury room. Fifteen-minute breaks usually meant a half-hour.

Conversation grew more personal. Juror No. 5, the retired teacher, said she'd had a hard time staying awake in court the day before. Somebody warned she could get fined for contempt of court.

The jurors of Courtroom 35 conspired to kick the chairs secretly of anyone nodding off. An us-against-them attitude emerged -- them being anyone not on our jury, lawyers and criminals alike. "Ain't none of us gonna get fined for dozing" reassured a large, matronly juror who worked at the Federal Trade Commission.

Other than the recurring topic of the lotteries -- specifically playing your jury number for good luck -- the conversations showed increasing signs of a group identity. The case forced us into a corner -- together.

Despite long hours of judicial nitpicking the day before, we started Day 3 agreeing the case -- any case -- was better than the somnambulism of the jury lounge. Jurors not on a case must report to the lounge at 9 a.m. Others arrive according to the judge's instructions. Judge Scott didn't need us until 11 that morning. By the time we got there, jurors in the lounge had already had a couple hours of ennui, along with the buzz of game shows and soap operas filtering out from the TV areas.

In our jury room, other than read, talk or -- conspicuously -- use one of the two small bathrooms that never had paper towels, there wasn't much to do either. Talk was cheap entertainment. We killed some time mapping out a way for an elderly juror to take the Metro from Southwest rather than drive to the courthouse and pay $5.50 to park.

Juror No. 12, increasingly our comic relief, took some teasing about his fast feet. "I was standing next to him out front, trying to catch a cab," said another juror. "Turned for a second and he was two blocks gone." No. 12 was embarrassed. "I ain't comfortable walking slow," he said, blowing smoke from the side of his mouth. "Especially not around no courthouse."

Speculation was rampant on the strategies attorneys use to choose members of the juries. Although social scientists have tried to refine the process with their empirical data, the process remains part typecasting, part hunch and part mystery. Some jurors felt "violated" by the voir dire ("to see and to say") process, in which attorneys question jurors at large or individually to assure impartiality.

Other jurors took personally the preemptory challenges that allow attorneys to reject jurors for no special reason. Although jurors may not be anxious to sit in judgment of someone else, they don't want to feel they're not good enough for it.

Judge Scott repeatedly told jurors during selection not to give it a second thought if they're spiked. Patting the shine on the top of his head, he'd say "if attorneys didn't like bald men, I'd have never made it to this bench." Court scuttlebutt had it that prosecutors wanted jurors with a stake in the community and traditional family ties; defense looked for signs of compassion and less conventional home lives. Both wanted impartial jurors -- impartial to their sides.

But we still couldn't talk about what we were burning to talk about: the case. So we talked around it.

"What about that Goetz fella in New York? What would you've done?" asked one of the quiet jurors. (The defendant in our case allegedly had pointed a 38-caliber, nickel-plated handgun at three victims and robbed them.)

Someone read aloud a headline about a D.C. man arrested a couple nights earlier for bashing in his wife's skull. A small woman who'd almost gone unnoticed for three days spoke up: "That man didn't look like he was right in the head, the way he kinda slumped to one side when the TV showed police arresting him." She lived in the killer's neighborhood, knew the victim's mother, had seen a lot of crime. She said she'd lock him up.

Then there was the 15-year-old kid in Virginia, tried as an adult and convicted of shooting and killing a schoolmate. The judge sentenced him to 15 years in prison. "That boy's gonna come out bitter and mean," said another juror. "Where's the justice then?"

Nobody said judging others comes easy. But, according to national statistics, these jurors' demographics (13 blacks and two whites, including alternates; 10 women; 11 past 50; most with marginal financial security) would make them "Most Likely to be Victims of Crime." Most of them lived where crime festers in the streets. They'd seen too much to give it a break.

Juror No. 11, a motherly version of Nell Carter, brought up Terence Johnson, the Prince George's County youth convicted a few years back of killing two police officers with one of their guns. "Some children are just no good," she said, encouraged by an amen or two. "There ain't much a parent can do sometimes. Children today are different than children when I was growing up." Thoughts focused on the young man seated out in the courtroom. "I knew better than to talk back to my parents."

"I still better never talk back to mine," said Juror No. 4, in her thirties, the youngest of the women there, an employe of the National Education Association.

Anxieties began to surface as cross-examination wound down. Conversation the last afternoon before deliberations bordered on bizarre. Someone mentioned the Soledad trial in California years ago that ended in a bloody shootout. Another recalled a Chicago trial where the defendant shot and killed the judge and prosecutor.

And there was court lore about "the defendant who smuggled in a plastic bag of feces and splattered the judge and jury," reminded one juror. "Do you think Judge Scott packs a pistol under his robe?" wondered someone.

The most sobering moment comes after the attorneys' closing arguments and instructions on the law from the judge. Alternates are dismissed and the jury retires to deliberate a verdict. Criminal cases require unanimity for conviction or acquittal.

Suddenly, the topic to be discussed was the defendant's guilt or innocence. No holds barred. An entire jury had been dismissed from deliberations earlier in the week, we were reminded, when two of the jurors got into fisticuffs over deliberations. Each of us wondered if he was alone in his opinion. The case seemed open-and-shut, with three credible eyewitnesses making "no doubt" identifications. But was it?

After four days of pent-up opinions, no one wanted to speak first. The foreman -- we elected the guy who missed on the lottery with his jury number by one day -- asked for a volunteer. No takers.

"I have no doubt he's guilty on all counts," the foreman's voice broke the silence. Immediately, everyone spoke simultaneously, relieved -- except for two -- to be in agreement. The two holdouts were willing to be convinced. "Let's not agree too quickly here," warned the foreman, looking at his watch, "or we won't get a free lunch from the court."

After the sequestered lunch, the foreman sent a note to the judge announcing we had reached a unanimous verdict.

The 15 minutes before we were called into the courtroom were nervous ones. "You should know," declared the foreman, "that the defense attorney will probably ask that we be polled. If she does, each of us will have to stand up and say he's guilty."

Our final conversation was about fear. Some joking, yes, but at its heart was fear. "He," said someone, "could be back on the streets this afternoon, you know, knocking at your door."

"Don't you think Judge Scott'll turn us loose long before he turns him loose?" another juror chuckled nervously. "He ain't gonna blame us. We're just regular people like he is, 'cept we did what the law required us to do here," reasoned another juror.

Just the same, one said later he thought the court should issue all jurors identical dark glasses with fake noses and mustaches. Justice may be blind, he said, but that guy we convicted wasn't.