Some local authority duties apply regardless of whether the person has a priority need. These include the duties to prevent and relieve homelessness.
The local authority only has a duty to actually arrange accommodation if:
...the Person has or might have a priority need
Emergency accommodation
A local authority must secure interim accommodation if it has reason to believe a person might:
Be homeless
Be eligible based on their immigration status
Have a priority need
Have not made themselves intentionally homeless
The local authority does not need immediate proof or evidence to have a reason to believe someone might be in priority need. The information the person provides at an initial interview can be enough.
If the local authority refuses to provide interim accommodation, this can be challenged through judicial review in the High Court.
Long term accommodation
The local authority owes the person the main housing duty if it is satisfied they have a priority need and are not intentionally homeless. The duty normally arises after 56 days have passed.
The local authority must secure suitable temporary accommodation until the duty is discharged, usually through an offer of more settled accommodation.