When can police search my cell phone in California?

In general, police may not search your cell phone without a search warrant that specifies the device to be searched and what evidence is being searched for. Even if police seize your mobile phone when they arrest you, they cannot search the data on your phone until they get a warrant first.

However, police can lawfully search your cell phone without a warrant if you consent to the search or if you are on probation or parole.

Police may also be able to get around the warrant requirement if there are exigent circumstances, such as when a search is necessary to:

• catch a suspect who is fleeing;
• prevent evidence from being destroyed; and/or
• prevent imminent danger or bodily harm to someone.

In general, police must have a valid search warrant, based upon probable cause, before they can perform a cell phone search.

1. Can police perform a search of your cell phone without a warrant?

In general, no. The U.S. Supreme Court in Riley v. California has ruled that the police must have a valid search warrant, based upon probable cause, before they can perform a cell phone search.¹

This court decision is consistent with the Fourth Amendment of the U.S. Constitution which protects people from unreasonable searches and seizures by the government.

Note that if a California judge does issue a search warrant for cell phone data, the warrant must describe the specific:

• cell phone to be searched, and
• evidence that is being searched for.²

Police are said to conduct an illegal search if they:

• search a different phone than the one described in the warrant, or
• obtain evidence other than the evidence described in the warrant.³

Example: A judge issues a warrant that authorizes the police to search John’s cell phone for evidence related to certain gang activity.

The police execute the warrant and fail to find any gang related evidence. However, they do find naked images of children during the search.

Here, a prosecutor could not file criminal charges of child pornography against John. This is because the warrant authorizing the search did not say anything about a search for explicit images of a minor.

2. What about a warrantless search if there are exigent circumstances?

California law states that the police may search your phone without a warrant if there are exigent circumstances.⁴

“Exigent circumstances” exist when the police have to search a phone quickly in order to prevent:

• bodily harm or imminent danger to someone,
• the destruction of evidence of a crime, or
• the escape of a fleeing suspect.

Please note though that, in the United States Supreme Court decision that established the warrant requirement for cell phone searches, the police tried to justify a warrantless search by mentioning exigent circumstances.⁵

However, the court turned down that argument. This means that while exigent circumstances can still technically support a warrantless search of your phone, that exception to the warrant requirement may have its limitations.

CA law says that law enforcement can search your cell phone data without a warrant provided that you consent or agree to the search.

3. Can the police conduct a warrantless search if you consent?

Most often, yes. California law says that law enforcement can search your cell phone data without a warrant provided that you consent or agree to the search.⁶

But note that your consent must be given:

• freely, and
• voluntarily.⁷

For example, the police cannot search your phone if you agree to the search after:

• the police threatened you with physical force,⁸ or
• authorities said they had a warrant to search your phone (but really did not have one).⁹

4. What about searches when you are on probation or parole?

The police might be able to search the personal data on your phone, without a warrant, while you are on probation or parole.

People on probation or parole usually have to adhere to certain terms and conditions (for example, attending counseling or agreeing to obey the law).

One such condition is agreeing to warrantless searches by the police. If this is one of the terms of your probation or parole, then law enforcement can search your phone without a valid search warrant.

5. Can the police seize your phone after arresting you?

Most often, yes due to the search incident to arrest (SITA) doctrine. The police can generally seize your phone after they legally arrest you. They can also do so without a warrant.¹⁰

If the authorities do seize your phone, they can then apply for a warrant to search your phone if they have probable cause that it holds evidence of a crime.¹¹

6. What if the police conduct a warrantless search?

If the police search your phone without a warrant, or without authority to do so under a warrant exception, then you have the legal right to file a “motion to suppress evidence” under Penal Code 1538.5.

A motion to suppress evidence is a pretrial motion where you or your criminal defense attorney asks the court to exclude evidence because it was gathered from an illegal search.¹² Note that the “exclusionary rule” is the law that states a judge should exclude evidence from a case if it was obtained illegally.

If a judge grants your motion, then the prosecutor is barred from using any evidence that was taken against the law.

7. Should you contact a criminal defense lawyer?

Yes. If the police searched your cell phone, you should seek legal help from a defense attorney or law firm.

The law in this area is complex and it is often changing. A skilled defense lawyer will help break down and explain the laws and rules that apply to your case.

A lawyer can also advise if the police conducted a legal search.

If the facts suggest that a search was not proper, your criminal defense attorney can file a motion to suppress evidence on your behalf.

The motion could ultimately lead to a reduction in your charge or an outright dismissal of a charge.

In our experience, people represented by a defense counsel have greater protection against unlawful searches and seizures.

Additional reading

For more in-depth information, refer to these scholarly articles:

• Seizing a Cell Phone Incident to Arrest: Data Extraction Devices, Faraday Bags, or Aluminum Foil as a Solution to the Warrantless Cell Phone Search Problem – William and Mary Bill of Rights Journal.
• Traffic Ticket Reasonable, Cell Phone Search Not: Applying the Search-Incident-to-Arrest Exception to the Cell Phone as Hybrid – Drake Law Review.
• Protecting the Privacies of Digital Life: Riley v. California, the Fourth Amendment’s Particularity Requirement, and Search Protocols for Cell Phone Search Warrants – Boston College Law Review.
• Password Protected – Can a Password Save Your Cell Phone from a Search Incident to Arrest – Iowa Law Review.
• The Post-Riley Search Warrant: Search Protocols and Particularity in Cell Phone Searches – Vanderbilt Law Review.