Statistical analysis is now used into many aspects of legal practice, from jury selection to establishing or challenging evidence, yet most statisticians know as little about legal procedure as the average lawyer knows about statistics. Statistics and the Law was written as a handbook to aid statisticians who may be invited to appear as an Expert Witness on a court case, to help them decide whether or not to accept that role, and, if they do accept. how to do a good job.
The first section explains what an Expert Witness is, what role they play in the legal system, and ethical issues involved in being an Expert Witness. It includes an essay by Michael O. Finkelstein and Bruce Levin on what qualifies a person to be designated an Expert Witness by the court, an essay by Kadane on ethical issues in being an Expert Witness, and several court decisions (Fry v. United States, Daubert v. Merrell Dow Pharmaceuticals, Kumho Tire Co. v. Carmichael, Panitz v. Behrend) in which expert witnesses appeared.
The remainder of Statistics and the Law follows a similar format, as explanatory essays and court decisions are used to introduce the most common types of cases in which statisticians are often called to be Expert Witnesses. Part 2 covers age and racial discrimination in employment and part 3 covers jury discrimination (violations of the principle that the jury selection process should not discriminate against potential jurors on the basis of race, sex, etc.), with special consideration of juries for cases in which the death penalty may be imposed.
Part 4 looks at a variety of legal issues in which statistical expertise is relevant. The first involved whether electronic draw poker requires skill to play: if not, draw poker machines are illegal gambling devices. Other cases considered in this section include that of a student accused of cheating on an examination, the method used to select who would be audited for state sales tax compliance, an accusation of ballot-box tampering, the usefulness of instruments designed to predict whether a violent sexual offender is likely to be a repeat offender, and a case of alleged patent misconduct.
Part 5 looks at the differences between British and American law, then discusses several cases from the United Kingdom. The first involved mothers accused of smothering their children and passing it off as “cot death” (SIDS), which Kadane compares it to the 1968 Collins case in California. In both, certain correlated facts were assumed to be independent, resulting in faulty reasoning which assigned a high degree of improbability to events (multiple crib deaths in the same family, a variety of circumstantial evidence linked to two defendants) which were not really that uncommon once the correlation was taken into account. Finally, Peter Donnelly explains an interactive approach he used to explain Bayesian statistics to a jury, followed by two court decisions which essentially invalidate his approach.
Statistics and the Law is an excellent introduction to legal issues for statisticians and requires no special legal expertise to understand. It would also be a good source of supplemental readings in statistics course, because students are often interested in practical applications of the material they are learning and this text presents both the statistical and legal issues with admirable clarity.
Joseph B. Kadane earned his PhD in Statistics from Stanford University and taught at Yale University and worked at the Center for Naval Analyses before joining the faculty at Carnegie Mellon University, where he is presently Leonard J. Savage University Professor of Statistics and Social Sciences Emeritus. His previous books include A Probabilistic Analysis of the Sacco and Vanzetti Evidence, Bayesian Methods and Ethics in a Clinical Trial Design, and Rethinking the Foundations of Statistics.
Sarah Boslaugh (firstname.lastname@example.org) is a Performance Review Analyst for BJC HealthCare and an Adjunct Instructor in the Washington University School of Medicine, both in St. Louis, MO. Her books include An Intermediate Guide to SPSS Programming: Using Syntax for Data Management (Sage, 2004), Secondary Data Sources for Public Health: A Practical Guide (Cambridge, 2007), and Statistics in a Nutshell (O'Reilly, 2008), and she served as Editor-in-Chief for The Encyclopedia of Epidemiology (Sage, 2008).