Detention General Instructions

The Home Office Detention General Instructions is a policy manual published for use by Home Office staff responsible for making decisions about immigration detention. The Home Office previously published Enforcement Instructions and Guidance (EIG) which addressed the same topics. The EIG has now been withdrawn.

The Detention General Instructions policy provides guidance on the powers to detain, decisions to detain and levels of authority to detain, detention procedures, how often detention reviews should be carried out, factors influencing the decision to detain and criteria for detention in prison, among other matters. It also addresses the use of detention for people detained with criminal convictions, pregnant women, vulnerable adults termed “adults at risk” and children impacted by detention.

The Detention General Instructions are useful reading for visitors to understand Home Office guidance on the powers and limitations of detention as well as how these should be adhered to by Home Office staff when making initial decisions to detain and decisions to maintain detention.

It’s starting point is that there should be a presumption in favour of bail and “Detention must be used sparingly, and for the shortest period necessary” (Detention General Instructions, page 7).

It outlines the limitations of detention in accordance with domestic law and the European Convention of Human Rights (ECHR). These are known as "the Hardial Singh principles", taken from an early immigration detention case. These principles are also outlined in Lawfulness of Detention. For ease of reference, these principles are:

1. The Home Office must intend to remove or deport the person/prevent unauthorised entry and can only use the power to detain for that purpose;

2. The person may only be detained for a period that is reasonable in all the circumstances;

3. If, before the expiry of the reasonable period, it becomes apparent that the Home Office will not be able to remove the person within a reasonable period, it should not seek to exercise the power to detain;

4. The Home Office should act with reasonable diligence and expedition to effect removal.

The Detention General Instructions have been updated to take account of section 12 of the Illegal Migration Act 2023. Section 12 permits detention for a period that the Home Office considers “reasonably necessary” in order to make a decision on an individual’s removal or to actually remove them. This impacts the third and fourth principles outlined above such that:

“It is for the Secretary of State, rather than the courts, to determine what is a reasonable period of detention in order to enable the specific statutory purpose to be carried out (for example, to enable the examination, decision, removal or directions to be carried out, made or given), subject to any statutory limitations. This emphasises that the Secretary of State is the primary decision maker who is in possession of all the facts surrounding a person’s detention. Therefore, in reviewing any unlawful detention claims, the Courts should approach their task by examining the reasonableness of the Secretary of State’s assessment, rather than by substituting their own assessment of the reasonableness of a period of detention.” Detention General Instructions, pages 9-10.

This section of the Detention General Instructions is useful reading to understand how the Home Office see’s this change introduced by the IMA affecting previously applied principles on detention. As this change takes more effect, what is “reasonably necessary” is likely to be subject to legal challenges which scrutinise the Secretary of States assessment of what is reasonable.