Henry Fonda's valiant one-man stand to save a boy from the electric chair in Twelve Angry Men would have failed to convince a real jury of his innocence, research published yesterday suggests.
In the 1957 film, Fonda's softly spoken character used subtle arguments to persuade the other 11 jurors that the defendant may not have murdered his father. But, in reality, he would have been drowned out by a dominant jury member and the boy found guilty.
Professor Simon Garrod, of the University of Glasgow, told the conference that his research showed juries were "not good arrangements for gaining true consensus".
His paper, published by the Economic and Social Research Council, also argued that groups of more than seven do not reach unanimous decisions. "In large groups, dominant speakers exert much more influence than others and people are not especially influenced by those they directly interact with," he said.
Professor Garrod said his research, which included studies of how large and small groups made decisions, might explain "perverse verdicts" which ignored common sense and why larger juries were more likely to fail to reach a consensus than smaller juries. "In large groups, the communication is more like serial monologue with each speaker broadcasting information in turn to the group as a whole. This explains why dominant speakers, who broadcast the most information to the group, have such a strong influence," he said.
Under the Contempt of Court Act it is illegal to conduct research using real juries because of the risk of "contaminating" deliberations. So Professor Garrod's research will help those who need to understand how a jury reaches its verdict. Some lawyers argue the British system should be reformed so that juries have to give reasons for their verdicts.
Lord Justice Auld, who is reviewing criminal courts for the Government, is also looking at the workings of juries. He is due to present his findings shortly.
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