Professionals' guide to interpreting statistics launched

Legal professionals are being offered free copies of a new guide to interpreting statistical evidence in criminal law cases.

Jointly written by professors of law, statistics and forensic science, "Case Assessment and Interpretation of Expert Evidence" is the last in a series of four practitioner guides published by the Royal Statistical Society
under the general title "Communicating and Interpreting Statistical Evidence in the Administration of Criminal Justice".

The publications outline best practice for the evaluation and interpretation of evidence in criminal justice, as well as illustrating the common pitfalls those not well-versed in probabilistic reasoning can make.

Written for judges, lawyers, forensic scientists and expert witnesses, with funding from the Nuffield Foundation, the series is authored by Professor Paul Roberts, Professor of Criminal Jurisprudence at the University of Nottingham, alongside Professor Graham Jackson (Abertay University) and Professor Colin Aitken (University of Edinburgh).

The guides include case studies where statistics have been used in court, including real-life examples of where misunderstood or misleading probabilities have led to unsafe convictions.

The RSS is offering hard copies of the guides free to those in the legal profession, as well as making them available online at no charge at www.rss.org.uk/statsandlaw. Those who wish to be sent a hard copy of the new guide should email rss@rss.org.uk with their contact details and required number of copies. Similar requests for copies of earlier guides are welcome subject to availability.

Commenting on the launch of the new guide, Professor Aitken, who chairs the RSS's section on statistics and the law, said: “There is a long history of misunderstandings relating to statistical information and probabilistic reasoning which have contributed towards serious miscarriages of justice. It is vital that everybody involved in criminal adjudication is able to deal correctly with these important contributors to the administration of criminal justice.

“The objective of the guides is to equip forensic practitioners to become responsible producers and discerning customers of statistics and confident exponents of elementary probabilistic reasoning.”