The question of when police can lawfully search a cell phone for evidence of a crime has been the subject of much debate.

Cellphones, after all, are effectively mini-computers that may contain a wealth of information, and the fact that we carry these devices on our person could make it that much easier for law enforcement and prosecutors to uncover evidence to convict you of a crime.

In most cases, police must obtain a valid search warrant to search the information on your cell phone.

The question is whether the personal information on your cellphone is protected by the Fourth Amendment, especially during an arrest.

If you are already under arrest on suspicion of a crime in California, can police search your cell phone without a warrant in the same way they might search your vehicle? And if so, when is it legal for them to do so—and when is it not legal?

You might be surprised to learn that in most cases, police cannot legally search your cell phone unless they obtain a warrant first.

In most cases, police will need a valid search warrant to search the data on your cell phone in California. This fact was clarified by a landmark Supreme Court case in 2014, Riley v. California.

However, there are some exceptions to the rule that police need the warrant to search your mobile phone. These include getting your consent and if police can show there was an immediate need to do so to:

• prevent the imminent destruction of evidence,
• help someone who is seriously injured or threats of harm,
• to pursue a fleeing suspect.

Also, while police may not search the data on your phone without a warrant, they could seize your phone if you have been arrested and hold it until they can get a warrant to search it. Our Los Angeles criminal defense attorneys will review California's laws and how they apply to cellphone searches.

Overview of Riley v. California

In Riley v. California, the United States Supreme Court considered two separate cases involving police searches of cell phones during arrests.

In the first case, a man named David Leon Riley was pulled over for expired registration tags on his car. A search of his vehicle turned up two guns, and Riley was subsequently arrested on weapons charges.

While Riley was in police custody, an officer took his cell phone and searched it without a warrant. The officer found photos and videos that linked Riley to gang activity, and he was then charged with additional crimes related to his gang affiliation.

The United States Supreme Court ruled that police will need a warrant to search someone's cell phone.

In the second case (United States v. Wurie), a man named Brima Wurie was arrested on suspicion of selling crack cocaine. A search of his cellphone revealed photos and videos that linked him to drug dealing, and he was subsequently convicted of drug crimes.

Both Riley and Wurie appealed their convictions because the police had unlawfully searched their cellphones without a warrant.

In both cases, law enforcement justified the warrantless search using the “search incident to arrest” (SITA) doctrine, which held that police might conduct a warrantless search of a person within the scope of their reach (e.g., the arrestee's pockets) to protect themselves from possible hidden weapons and preserve evidence.

When Riley made its way to the Supreme Court, the Court combined it with Wurie's case to consider whether law enforcement has the right to the warrantless search of cellphones under SITA?

The normally divided court decided unanimously in favor of Riley and Wurie, stating that a cellphone cannot be considered a weapon, so police aren't protecting themselves by taking it, and any related evidence on the phones could have been preserved without searching the phones.

Thus, searching the cellphones violated the defendants' Fourth Amendment rights. Chief Justice John Roberts summed it up this way: “Our answer to the question of what police must do before searching a cellphone seized (during) an arrest is simple – get a warrant.”

When Can Police Lawfully Search Your Cellphone?

Riley v. California cleared up a great deal of ambiguity regarding cellphone searches, not just in California but in other states that had previously supported warrantless cellphone searches under SITA.

So what does this mean for you? Under what circumstances can police now lawfully search your cell phone if you're arrested? Thanks to the Supreme Court ruling in Riley, in the vast majority of cases, there are only three instances in which police may lawfully search your cellphone:

• When you permit them to do so. If the police ask to search your cellphone and you say yes, you are effectively waiving your right to privacy, and anything on the cellphone may then be used as evidence'
• If they obtain a warrant. If police truly believe they have reasonable cause to search the cellphone for evidence, and if they believe the evidence might be destroyed otherwise, they can request a warrant to search the phone, the same as if they obtained a warrant to search your home or your computer.
• If you are on parole or probation. In many cases, the terms of parole or probation allow law enforcement to conduct warrantless searches.

One technical point worth mentioning: the SITA doctrine still applies in California. Suppose law enforcement genuinely believes someone's life is in imminent danger, or that material evidence may be destroyed unless the cellphone is searched. In that case, they may search the cell phone without a warrant.

However, thanks to Riley v. California, it's become much more difficult for police to justify this claim. If you are arrested, you have the right to deny police access to your cellphone unless they obtain a warrant.

What is the Warrant Requirement for Cell Phones Searches by Police?

In most cases, the police need a valid search warrant to search the data on your cell phone.  They must apply to a California or federal judge for the search warrant.

A judge will issue search warrants for cell phone data if they have determined “probable cause” to believe a felony has occurred, and the search will produce evidence about the crime.  A valid search warrant for a cell phone has to describe the following specifically:

• the cell phone or other mobile device that will be searched, and
• the specific evidence that is being searched for.

Suppose the police search cell phones or mobile devices that are not listed in the warrant or discover evidence that was not described in the warrant? In that case, that evidence can't be used against the defendant as it's considered invalid.

If your cell phone was searched without a warrant, we may be able to get the evidence excluded.

If you are accused of a crime after an illegal cell phone search, you have the legal right to challenge any evidence from that search. If the evidence is crucial to the prosecution's case, it might be possible to get it excluded, and you may be able to get the charges reduced or even dismissed.

We may be able to file a Penal Code 1538.5 motion to suppress evidence as part of the California pretrial process.

This is a request to the judge to toss out any evidence acquired through a search of your phone without a warrant and didn't fall within the exceptions discussed above.

If you believe your rights have been violated, speak to an experienced California criminal defense attorney. Eisner Gorin LLP is based in Los Angeles, California. You can contact us for an initial case review by phone or use the contact form.

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