The recent Pennsylvania trial court ruling striking down the state’s voter ID law is only the most recent instance where a court relied heavily on evidence produced by social scientists and statisticians. 

Dr. Lorraine Minnite is an associate professor at Rutgers-Camden and a well-known expert on vote fraud.  Minnite was brought in by the plaintiffs to examine the content of the legislative debates regarding the need for voter ID and the prevalence (or not) of voter fraud in Pennsylvania.  Her report starts at page 20 here and is an entertaining read for anyone interested in legislative intent.  The court determined, for instance, that there appeared to be a “legislative disconnect from reality” (pg. 41 of the decision), and Minnite shows that, whatever the merits of voter ID, the speculations of legislators often outstripped reality.

To read more about this case, see this recent NYT article.