There used to be two certainties about jury service: if you turned up at court in a suit and tie clutching a rolled-up copy of The Daily Telegraph, you wouldn’t be selected; and, if you were selected, you would be obliged to maintain an omertà-like silence about any cases you heard.

No longer. The former belief was probably apocryphal anyway. As for the latter, far from not being able to talk about cases, some jurors now don’t seem able to keep quiet.

Jurors are forbidden under the Contempt of Court Act 1981 from revealing anything about their deliberations, but they can talk about other aspects of the trial. Last October two jurors in the Jill Dando murder trial said on BBC television they thought they had reached the wrong conclusion at the original trial. In the light of new evidence, Barry George should not have been convicted of the TV presenter’s murder, they said (a view subsequently shared by the Court of Appeal when it ordered a retrial).

More recently, two jurors in the trial of the childminder Keran Henderson have spoken about their concerns that she should not have been convicted for shaking to death a baby in her care. One was quoted on BBC radio saying that the trial had been “an absolute shambles” and jurors had “struggled” to stay awake at times.

Mike Seckerson, the foreman in the Henderson trial, is writing a book about the case, passages of which wouldn’t be out of place in a racy crime novel (“I suss the scene: the usual boxes, benches, wigs and the ominous, anachronistic garb of Santa and his helpers, the four lawyers of the apocalypse clad in vulturous black . . .”).

Lawrence Archer, the foreman in another prominent case, the ricin terror plot, is planning a book of his own, which promises to be a rather more sober read. The ricin trial lasted six months and after a month’s deliberating, the jury acquitted four of the five men accused of plotting a terror attack. Almost immediately their verdict came under attack by the police and others in the media. “There was a suggestion in some quarters we’d been duped, that the accused had got away with it, rather than been acquitted on the basis of the evidence,” Archer says.

A month later, it was reported that the four acquitted men were to be deported to Algeria, despite concerns that they would be imprisoned or tortured on their return. Archer and some of his fellow jurors were outraged. “We felt our decision was being ignored,” he says. “We wanted justice for the guys we’d cleared. We believed they were innocent and were very, very worried about what would happen to them if they were deported.”

Since then, he and two other jurors have become increasingly vocal in their criticisms of government’s treatment of the men (threatened with deportation; held in prison; subjected to stringent control orders). He has even formed what he admits is a somewhat unlikely friendship with one of the four former defendants (“We see each other about once a week”), and visits another who is being held in Long Lartin prison.

Archer, 53, a telephone engineer who describes himself as “Mr Normal”, is more surprised than anyone at his late flowering as a political activist. “Normally, I’m quite a passive person. I don’t usually get involved in this kind of stuff,” he says mildly.

Michael Mansfield, QC, who successfully defended in the ricin case, says Archer and his fellow jurors’ spirited defence of the integrity of their verdict is “entirely responsible and courageous”.

He is less convinced, however, about the wisdom of jurors going to the media when they think that the jury came to a wrong decision. “The classic case was the O. J. Simpson trial, when the jury came out saying: ‘We had to acquit him, but we think he was guilty’.” The jury reaches a collective decision and, however well motivated, if individual jurors criticise the decision afterwards, it undermines the integrity of the jury system as a whole, he says.

Mansfield’s concerns are shared by other defence lawyers. Much of the strength of the jury system stems from its mystique, they point out. No one really knows how juries work, they just do. Jane Hickman, of Hickman Rose, cautions that if jurors start arguing among themselves in public after a verdict, opportunistic politicians will seize on this to limit their use in complex or controversial cases. “Juries’ deliberations are kept secret for very good reason and it’s in all our interests that that’s preserved,” she says.

Although some defence lawyers believe the increasing trend of jurors to go public is part of the “celebrity culture” (“they want their 15 minutes . . .”), Mansfield is more charitable. He suspects they end up talking to journalists because no one else wants to listen. He would like the appeal system reformed to include a formal channel that jurors could use to bring their disquiet about a verdict to the attention of the court.

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