Can police seize your phone?

Yes. Police have several powers to seize mobile phones, most commonly under s.19 PACE 1984 (seizure during a lawful search of premises), s.32 PACE (search following arrest), or under a warrant. Seizure does not automatically mean the phone will be searched: accessing its contents requires separate legal authority, usually a warrant.

The law

Police and Criminal Evidence Act 1984, Section 19. Seizure of anything on premises that an officer has reasonable grounds to believe is evidence of an offence under investigation.
Police and Criminal Evidence Act 1984, Section 32. Search of arrested person and immediate vicinity: phone can be seized as potential evidence.
Regulation of Investigatory Powers Act 2000, Section 49. Power to require disclosure of encryption keys or passwords in serious investigations. Failure without reasonable excuse: maximum 2 years.

What to do

Ask which specific PACE power is being used to seize your phone and request a property receipt.
You are generally not required to provide your PIN in ordinary criminal investigations: note this politely but firmly.
If a s.49 RIPA notice requiring your PIN is served in a serious case, seek legal advice immediately before deciding whether to comply.
Keep a record of when the phone was taken and follow up in writing if it is not returned within a reasonable period.
If you believe the seizure was unlawful, contact a solicitor who can apply to the court for its return.

In detail

A mobile phone is personal property, but it is also potentially a repository of significant evidence. Police have powers both to take possession of a phone and, separately, to access its contents. These are distinct steps governed by different legal provisions.

Seizure of the physical device

Under s.19 of PACE 1984, a constable who is lawfully on premises may seize anything they have reasonable grounds to believe is evidence of an offence under investigation, or has been obtained through the commission of an offence, provided it is necessary to seize it to prevent it being concealed, lost, altered, or destroyed.

Under s.32 PACE, following an arrest, an officer may search the arrested person and their immediate surroundings for anything that might be used to assist escape or that is evidence of an offence. A phone may be seized under this power.

Under s.18 PACE, after arrest for an indictable offence, officers can search any premises the arrested person was in or controlled, and seize items found there.

Phones can also be seized pursuant to a specific search warrant issued under s.8 PACE or under other statutes (for example, the Proceeds of Crime Act 2002 where assets are being investigated, or the Terrorism Act 2000).

Accessing the phone's contents

Seizing the physical device and accessing its digital contents are separate legal acts. Accessing the contents of a phone requires either:

Consent from the owner: the police may ask you to provide your PIN or biometric to unlock the device. You are not legally compelled to provide a PIN, though in terrorism cases or under certain investigatory powers legislation this position is more complex.

An order under s.49 of the Regulation of Investigatory Powers Act 2000 (RIPA): in serious cases involving national security, serious crime, or economic well-being, a notice can be served requiring disclosure of a key or password. Failure to comply with a s.49 notice without reasonable excuse is an offence under s.53 RIPA. The maximum sentence is two years' imprisonment (five years in national security cases).

A warrant or production order: in most investigations, police obtain a digital seizure and examination warrant or apply to a court for an order authorising examination of the device.

Data retained after examination

Under the guidelines issued by the National Police Chiefs' Council and the College of Policing, once a phone has been examined and data extracted, the data must be handled in accordance with UK GDPR principles. Irrelevant private data should not be retained. The Investigatory Powers Act 2016 governs longer-term surveillance and bulk interception powers.

Your rights on seizure

You are entitled to be told which power is being used to seize your phone. You can request a receipt for property taken. You should be given a certificate of seizure or property receipt at the time (or as soon as practicable). If the phone is not required as evidence or is no longer needed for investigation, it should be returned. You can challenge retention through the courts if the police refuse to return it.

Providing a PIN: the position on compulsion

Outside terrorism and national security contexts, there is no general legal requirement to provide your PIN. Refusing to provide a PIN is not, in ordinary criminal investigations, a criminal offence. However, refusal can be a factor in the overall investigation and may delay the return of your device.