Suppose that Police officers came to the home address of a person A, looking for a person B who does not reside at our address. Suppose B is the adult child of A. Can they still enter the premises to undertake a search even though they have been told by me the owner of the property that B does not reside there?
Police cannot enter private property subject to a number of exemptions:
- they have a search warrant, or
- when in close pursuit of someone the police believe has committed, or attempted to commit, a serious crime, or
- to sort out a disturbance, or
- if they hear cries for help or of distress, or
- to enforce an arrest warrant, or
- if invited in freely by the occupant, or
- under various statutes which give the police powers of entry (not necessarily by force) into a number of different kinds of premises.
In the US police officers may not lawfully enter a dwelling unless one of the following situations apply:
- A resident consents to their entry;
- The officer has a properly authorized warrant, based on probable cause;
- One of the exceptions to the warren rule applies, particularly exigent circumstances This covers the case where officers actually saw a suspect fleeing into the building, circumstances where officers have good reason to believe that a third person or people is at risk unless they enter, and other situations in which courts have held that a delay to seek a warrant is unacceptable.
If an officer enters unlawfully, any evidence found will be inadmissible in court (exclusionary rule) and any evidence later found by means of information discovered by the unlawful entry is also inadmissible (fruit of the poisoned tree) unless an exception to exclusion, such as "inevitable discovery", applies.
The law in the various parts of the UK will be different, at least in detail, but I suspect the broad outline is similar.