For civil suits, a major point of jury research is leveraging settlements; for prosecutions (and, infrequently, major civil suits, especially class actions), jury selection.
Civil trial attorneys have tremendous interest in jury behavior, not for reasons of influencing juries, but in order to encourage settlements and minimize resultant settlement severities. About 100 million criminal and civil suits are filed in U.S. state and federal courts annually (55 million of these are traffic-court related). Counting only non-criminal and non-traffic-related suits, about 17 million civil suits occur annually. Of these, less than 3 percent of U.S. civil suits are tried before a jury until verdict. In civil cases, anticipated jury behavior serves as an important factor in the choice to settle before verdict (see, for instance, http://www.juryverdictresearch.com/ ),
For example, in U.S. medical malpractice suits, Jury Verdict Research data may indicate a $1 million mean verdict (skewed high due to self reporting and lack of reporting of the subsequent effects of appeals) and the National Practitioner Database may indicate $235,000 for mean final judgment verdict and $125,000 for settlement (these are actual nationwide means for 2003). Such ranges (adjusted for venue and injury details) establish settlement ranges, and verdicts are sought only in those suits that may establish undesirable precedents.
Similarly, a little over 3 percent of U.S. criminal suits are tried before a jury until verdict. The great majority of criminal suits are disposed by plea. For those tried before a jury, the interest in jury behavior is usually addressed in voir dire, an extremely important process when the defendant has the resources to influence the process.