Edward J. Imwinkelried.
The use of expert testimony at trials is not only widespread; its use also appears to be increasing. In a Rand Corporation study of California trials in courts of general jurisdiction, the researchers found that experts appeared in 86% of the trials; and on average, there were 3.3 experts per trial. A more recent study reported that the average has risen to 4.31 experts per trial. One commentator has asserted that in the United States, trial by jury is evolving into trial by expert. That assertion is hyperbole, but it is undeniable that the quality of expert testimony is now a major determinant of the quality of the outcomes at American trials.