This week we look at the importance timing of arrest has on the overall outcome of a successful case.

In this series, we preview sections of Blackstone's third edition of the Senior Investigating Officers' Handbook. This book provides invaluable insight about the essential skills and responsibilities that a senior investigating officer needs to manage serious crime investigations, from the initial response through to crime scene examination and investigative strategies. PoliceOracle.com readers can enjoy a 20 per cent discount on the book with our special offer code at the end of this article.

Timing of arrests

Usually the sooner suspects are arrested the less chance and opportunity there is for them to destroy or contaminate evidence or interfere with witnesses. There may also be financial and resource-saving benefits in reducing costs by avoiding lengthy investigations. A duty of care for safeguarding the welfare and safety of the general public needs to be an overriding factor too.

Where there is an opportunity to make an early arrest based on available information, then usually it should be taken. The closer to the time the offence was committed the arrest is made, the greater an opportunity there is to recover forensic evidence or any other useful items or material. It also prevents the offender from concocting an alibi, threatening potential witnesses, destroying evidence or committing further offences. It provides victim and/or community reassurance, increases trust and confidence in the police, and prevents any temptation for people to ‘take the law into their own hands’.

However, the most advantageous time, date and place to make an arrest will depend largely on individual circumstances. There are a number of factors that may influence the decision, for example coinciding an arrest operation with a tactic to try and approach potential witnesses, who may be withholding information for fear of intimidation. There may also be a practical consideration of having to trace a suspect’s whereabouts in order to effect the arrest and some covert work may be required to ‘house’ them beforehand.

The ‘golden hour(s)’ principle suggests offenders are at their most vulnerable nearest to the time of the offence and more likely to make mistakes or admissions when interviewed. This is when they are less able to claim they ‘cannot remember’ what they were doing or where they were at the material time, especially if the time difference between offence and arrest is minimal.

The Core Investigative Doctrine states:

The decision about arrest timing depends on a number of factors. These should be kept under continuous review. If the circumstances should alter, the decision to make an immediate arrest or to delay it may have to be amended and the reasons for this recorded.

The timing of an arrest provides the investigator with an opportunity to plan searches of the suspect’s home address (or other premises) and their vehicles. It may also provide opportunities to recover incriminating or corroborating material before it is altered, disposed of or destroyed.

A search of a suspect’s premises may also identify property from other offences or intelligence that can be used to identify other offenders or associates. There are, of course, other ways in which to conduct searches of premises without the need to make formal arrests, such as by a search warrant. Section 8 of PACE as amended by sections 113 and 114 of SOCPA provides the grounds and procedure to be followed when applying for a search warrant for an indictable offence. It also provides a power to seize certain incriminating items.

About the authors

Former Detective Superintendent Tony Cook was a career detective and senior investigating officer with Greater Manchester Police until he retired in 2009. He is currently a PIP Level 3 and 4 Regional SIO Advisor with the National Crime Agency.

Andy Tattersall, formerly Detective Superintendent in Greater Manchester Police on the Force Major Incident Team, retired in 2007 after 33 years' service and became the first ever Support Staff SIO in charge of a new Homicide Support Unit.

Blackstone's Senior Investigating Officers' Handbook is designed specifically to meet the quick-reference needs of any officer conducting a serious investigation. The only portable step-by-step guide to the processes and actions involved in the role of a Senior Investigating Officer (SIO), it explains all the relevant procedures and instructions integral to the position in a clear and accessible style.