It was Gene Hackman's role as hard-nosed Rankin Fitch in the John Grisham-inspired film Runaway Jury that first exposed to a wide public the secret world of the jury consultant.
Hired by trial lawyers to crack the case, jury advisers have won claimants millions of dollars in damages by profiling the prejudices of jurors. Now the US-based consultants are in demand from British law firms who are using them to try to second-guess juries in major court cases in the UK.
In America, consultants are called in to challenge "unsuitable" jurors who are perceived as being unsympathetic to their client's case. Here in Britain, where the law does not permit such general challenges to remove jurors, solicitors use them to help assess mock juries so advocates can try out their lines of argument in front of a random group of members of the public. It is a development that many lawyers welcome, as it allows them to be more scientific in their appreciation of the role of the jury.
Alexandra Rudolph is a jury consultant who has worked on hundreds of jury trials in America including the Conrad Black trial. She worked with the defence team representing Jack Boultbee, a loyal lieutenant to Black, who was sentenced to 29 months' imprisonment for his part in the Hollinger fraud.
Ms Rudolph says she is now working in big cases over here. She says: "Jury profiling is a based on jury research, generally through the use of focus groups. More and more lawyers are using focus groups or mock trials to prepare their cases."
One of the biggest advantages of using mock juries is that it sidesteps the rules stopping anyone interfering with the work of an empanelled jury. In this environment the consultant can show lawyers how their court-room strategies risk alienating juries. "Quite often lawyers and jurors are not on the same page. What may be extremely important in the lawyer's eyes is entirely dismissed in the hands of the jury and vice versa," argues Ms Rudolph, who worked for four years with the US trial consultants Zagnoli McEvoy Foley and now runs a firm called Just Juries.
"When conducted properly," she says, "focus groups are enormously helpful in identifying case strengths/weaknesses, juror language, perceptions of key witnesses, credibility of the evidence, reaction to presenting attorney and effectiveness of defence and plaintiff arguments."
New Labour's obsession with focus groups has raised awareness of their value outside market research. David Price, a leading media lawyer based in London, is one of the first to have used mock juries in libel trials in this country.
Twelve members of the public are paid to attend jury sessions in his offices where they are asked to look at television programmes or newspaper articles in cases in which Mr Price is involved. "We try to create a environment as close to a jury room as possible," he says. "It can be very useful to see how the non-lawyer looks at a case. I can also pick up some ideas from outside the box, that will help shape my arguments in court. You might also get a general steer about how not to approach a live jury."
But other jury lawyers have yet to take advantage of the mock jury system. One lawyer from a famous London libel law firm said: "I might ask the secretary to look at the offending article or publication but that's about as much outside help as I have on the psychology of the jury."
Mr Price, who has used mock juries in eight of his cases, says that the process can also help him to advise a client as to whether their claim would be better heard before a jury or a judge sitting on his own.