In the UK it is not unlawful to drink and drive. It is only unlawful to drive while above the prescribed limit of alcohol or be unfit to drive through the amount of alcohol consumed.The prescribed limit also differs around the UK. Scotland, for example, has a stricter level than England, Wales and Northern Ireland.

Prosecutions of suspected drink drivers sometimes fail because the police fail to follow correct procedures.

As an ex-police custody sergeant, police trainer and now expert witness, Joanne Caffrey has conducted in excess of 1,000 evidential drink drive procedures, taught officers what they should be doing, and provided courts with reports for what the officers did or did not do.

Time and time again prosecutions fail because officers do not comply with basic fundamental principles and practices in law, or lack knowledge and confidence in which procedure they should be following.

Now, in this volume, Ms Caffrey outlines the real-life procedures for bringing a prosecution.She explains: “Law books are available which discuss the legislation and case law, but what this book brings to the reader is the holistic safer custody process to safeguard the prosecution and safeguard the detainee, preserving life whilst not losing evidence. I use my experience to draw upon real case examples of how prosecutions have failed against suspected drink drivers.”

The book is aimed at all police staff – from the point of scene attendance to arrest, transport and the custody unit ‘station procedures’. Defence and prosecution teams will also find it extremely useful to understand what should have occurred.

The book also reviews the working relationships between healthcare professionals, hospital staff and custody staff.

Ms Caffrey continued: “The principles apply to all UK police forces of England, Wales, Scotland and Northern Ireland, and those forces who have adopted the UK standards and expectations. Comparable practices and policies exist throughout the UK police services. Domestic laws may differ, but the practice delivery is to meet the UK standards for those detained at the hands of the state.”

Drink Driving: Police Custody Procedures is a must-read for any person involved in drink drive prosecutions, either as part of the defence or prosecution teams.

• Amazon: Hardback £30, Paperback £25, Kindle £9.99; ISBN 979-8866034208. To order Drink Driving: Police Custody Procedures please click here