Tom Williamson is a commander in the Metropolitan Police Force.
Less than six of the 400 or so names cited in the author's index of this book will be familiar to British readers. The absence of any reference to British experts (eg Gudjonsson) is a weakness and reflects the introspection and preoccupation within the US of so much literature in this field.
There is a token reference to the formation of the Metropolitan Police in London in 1829, but this book fails to recognise that since then there have been significant developments in UK policing and justice, and that psychology has shaped many of these changes. Its usefulness to British practitioners is limited.
The book is too dismissive of the risks for policing in using psychologists. However, at a time when the use of offender profiling has been castigated by an Old Bailey judge, Blau's chapter on the subject sounds a useful warning: the most limiting factor about psychological profiling is the amount of preparation necessary to accurately profile crime.
This book indicates that psychologists can contribute to many areas of law enforcement, but in purchasing these services from those who spread themselves too thinly such advice is likely to be shallow and probably misleading. Caveat Emptor.