@ Geoff Campbell
This is something that Private Eye has been covering for years - specifically, in complex financial fraud cases that require very long court cases.
With these types of trials, it’s been argued that the details of such cases are so complicated that when they are explained in a broad way, in order a lay person can understand, a lot of the wrong-doing is lost. In other words, you need to look at the fine details to be able to properly examine if the law was broken.
Here’s a director of the Serious Fraud Office speaking about his in 1997:
"The prosecutor strives to present a complex commercial fraud to a jury of lay people in a way that enables them to understand the intricacies of the commercial transactions and understand the documents, often the most convoluted and intricate sets of accounts," she said. "But this means having to prune a case to its bare essentials, losing, in the process, substantial elements of the total criminality alleged."http://www.independent.co.uk/news/sfo-wants-to-end-trial-by-jury-in-complex-financial-cases-1239577.html
This has been long debated in legal circles – for example:
“In 1986 Lord Roskill's Fraud Trials Committee did not find trial by a random jury a satisfactory way of achieving justice in cases of long and complex fraud. Lord Runciman's Royal Commission on Criminal Justice, which reported in 1993, was more cautious. It pointed out that no-one really knew how juries reached their verdicts because it was against the law to ask them. It recommended a change in the law to enable research to be carried out. Lord Justice Auld was quite clear, however, in his Review of the Criminal Courts in 2001. He said, in line with Roskill's favoured option, that in serious and complex frauds the nominated trial judge should have the power to direct a trial by himself and two lay members drawn from a panel established by the Lord Chancellor for the purpose, or, if the defendant so requests, by himself alone.“
http://www.barristermagazine.com/archivedsite/articles/issue25/staple.html