They were called the "giggle gang" — four alternate jurors in the John Edwards trial who wore the same-colored shirt to court on several days.

During nine days of deliberations, much attention was given to the merry band of alternates in the high-profile campaign finance case.

On Thursday, attention swung back to the jury itself, which found Edwards not guilty on one count. The judge declared a mistrial on the other five charges.

In the days before the verdict, reports that a young alternate juror had been flashing smiles at Edwards — the former North Carolina senator who was on trial for actions related to trying to hide his pregnant mistress during a presidential campaign — ricocheted far beyond the courtroom in Greensboro, N.C.

Hank Asbill has been a defense lawyer for 35 years — long enough to remember when Roy Black, the prominent attorney defending William Kennedy Smith in 1991 on rape charges, met and later married a member of that jury.

But Asbill says the color-coded T-shirts worn by the Edwards jury alternates represented something new under the sun.

"I've never seen this kind of conduct by alternates," says Asbill. "I think that that's unusual and strange. It's also unusual for alternates to be around the courthouse."

And despite the relatively benign showmanship of the Edwards alternates, there is actually considerable precedent for shenanigans in the jury pool at U.S. trials.

When Alternates Get Bored

Usually, a judge will let alternates go about their daily lives during deliberations and call them back to court if one of the regular jurors gets sick or drops out, Asbill says. And that's what finally happened Wednesday, when the trial judge in the Edwards case let them go home, on standby.

Asbill thinks those alternates were acting out because they just got bored.

After all, jurors are only human. In high-profile cases, the microscope on jurors can magnify lots of spots — even ones that aren't really there.

Take the case of Dennis Kozlowski, the former CEO of Tyco. Back in 2004, he was on trial for looting the company to pay for shower curtains, umbrella stands and a $2 million birthday bacchanal for his wife.

Austin Campriello was a defense lawyer in the case.

"There came a point in time where the jury was being excused, and one of the jurors ... was walking across the courtroom to go to the exit, and the prosecutors believed that they saw her give the defense table an 'OK' sign," says Campriello.

Newspaper reporters identified the elderly juror and dubbed her the " holdout granny." Campriello says Kozlowski's legal team didn't see it that way.

"We don't think she was sending us a message. We think she was flipping back her hair," says Campriello.

Whatever the case, the juror eventually told the judge she got threatening mail. So the judge declared a mistrial, after nearly six months, and the case had to start all over again, with a new jury.

Trial By Twitter

Trials have ended in disgrace lately because jurors are emailing, tweeting or otherwise social networking.

Earlier this year, a Florida man got three days in lockup for friending a female defendant on Facebook after he was called to serve on her jury.

Former prosecutor Steve Cohen remembers he was flummoxed by a more old-school kind of jury communication. After a long wait for a verdict in a triple homicide case, Cohen says, came this disconcerting development:

"We got a note from the foreperson. And the note said, 'Would it be possible for us to render a verdict and then the court hold the defendant and his family in the courtroom for one-half hour?' " says Cohen.

The judge followed up and learned that several jurors used the same New York subway route as the defendant's family.

"And it turned out they wanted a head start so that they could get home after they rendered a verdict. At that point, we knew they were voting guilty," says Cohen.

So, does the former prosecutor see that as a lesson of not reading too much into jury notes before we know what's going on?

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