Section 191 of the Housing Act 1996 provides that person is intentional homelessness if he has deliberately done or failed to do something in consequence of which he ceases to occupy accommodation which is available for his occupation and which it would have been reasonable for him to continue to occupy. This definition can be broken down into five elements.
The Elements of Intentional Homelessness
A person becomes homeless intentionally if (a) he deliberately does or fails to do anything (b) in consequence of which (c) he ceases to occupy accommodation (d) which is available for his occupation and (e) which it would be reasonable for him to continue to occupy (section 191(1) HA 1996).However, an act or omission in good faith on the part of a person who was unaware of any relevant fact shall not be treated as deliberate (section 191 (2) HA 1996).
In order for somebody to be intentionally homeless all of the elements of the definition must apply.
Deliberate act or omission
There must be a deliberate act or omission.
In order for an applicant to be intentional homelessness the act which led to the loss of their accommodation must have been deliberate. That is to say that despite being aware that the act or omission would lead to the loss of accommodation the applicant still went ahead on purpose with the act or omission. This means that acts or omissions which occurred as a result of a mistake or when an applicant was not aware of what they were doing should not entitle a council to treat them as intentionally homeless.
Acts Arising From Mental Illness, Substance Abuse, Duress
Paragraph 11.17 of the Code of Guidance states that an act or omission should not be considered deliberate where:
1. The act or omission was non-payment of rent which was the result of housing benefit delays, or financial difficulties which were beyond the applicant’s control;
2. The housing authority has reason to believe the applicant is incapable of managing his or her affairs, for example, by reason of age, mental illness or disability;
3. The act or omission was the result of limited mental capacity; or a temporary aberration or aberrations caused by mental illness, frailty, or an assessed substance abuse problem;
4. The act or omission was made when the applicant was under duress;
Acts Arising From a Mistake
The loss of accommodation must be in consequence of the act or omission
There must be a cessation of occupation, as distinct from a failure to take up accommodation
The accommodation must have been available for the occupation of the homeless person
This means that if the applicant would have had to leave the property anyway their deliberate act or omission cannot be treated as giving rise to the loss of the accommodation. The best example of this would be where a landlord wants to sell the property or move back into it. If the landlord evicts the tenant then the fact that the tenant had high rent arrears, which might even have been relied on in the possession proceedings, the tenant won't be intentional homelessness because the property would not have been available for him anyway.
The issues of whether a property would have been available for continued occupation and whether it would be reasonable to continue to occupy will often overlap. In In Haile v Waltham Forest LBC  the applicant had been living in a hostel for single people whilst pregnant. When the baby was born the property would have been unsuitable for her and she would have been required to leave. It was therefore arguable both unreasonable and unavailable for her continued occupation after the birth of the baby.
It must have been reasonable for the homeless person to continue to occupy the accommodation
An applicant cannot be intentionally homeless is the accommodation which they lost would not have been reasonable for them to continue to occupy. For instance if they were at risk of violence there or the property or the condition of the property made it unsuitable for them.
In Haile v Waltham Forest LBC  the Supreme Court upheld the decision of the majority in the House of Lords in Din (Taj) v Wandsworth LBC  that, in deciding whether accommodation was available and whether it would have been reasonable for the applicant to continue to occupy it, the authority had to consider the time when the applicant ceased to occupy the accommodation. In relation to those matters, the decision in Din was correct; if the definition is satisfied as at that time, it is immaterial under s.191(1) of the 1996 Act to consider subsequent hypothetical events.
However, Din was decided “on a basis accepted as common ground which involved an erroneous conclusion of law from undisputed facts”.  “The decision on the facts reflected the concessions made and the state of the law at that time… a case on similar facts would not now be approached in the same way.” 
This was because in Birmingham v Ali; Moran v Manchester  1 W.L.R. 1506 the House of Lords had held that “reasonable to continue to occupy” is a concept that looks to the future . Accordingly, “a person was homeless [at the date she ceased to occupy the accommodation] if he had accommodation which it was not reasonable for him to continue to occupy for as long as he would have to occupy it if the local authority did not intervene”  and .
Accordingly, the authority should ask whether, as at the date of giving up the accommodation it was reasonable for the applicant to continue to occupy for as long as he would have to occupy it if the local authority did not intervene”
In Haile v Waltham Forest LBC  the Supreme Court held that a later event after the deliberate act of omission which gave rise to an involuntary cause of homelessness will supersede the applicant’s earlier deliberate conduct, where in view of the later event it cannot reasonably be said that “but for” the applicant’s deliberate conduct, he would not have become homeless; in such cases, the applicant would not be homeless intentionally as the causal connection between his current homelessness and his earlier conduct will have been interrupted , .
Where the deliberate conduct remains a “but for” cause of the homelessness and there is an issue as to whether the chain of causation should be regarded as having been interrupted by a later event, the question will be whether the proximate cause of the homelessness is an event which is unconnected to the applicant’s own earlier conduct, in the absence of which homelessness would probably not have occurred , .
The consequence of the birth of the appellant’s daughter was that it could not be said, in relation to her earlier conduct in leaving the hostel, that “if she had not done that deliberate act she would not have become homeless”; the birth of the child meant that the appellant would be homeless, at the time when her case was considered, whether or not she had left the hostel when and for the reasons that she did; this analysis did not involve departing from the reasoning in Din (Taj) v Wandsworth LBC  in which there had been no such later causative event, merely a possibility that one might have occurred.