Fourth Amendment

Should Police Need a Warrant to Search an Arrestee's Cellphone?


This week, as Mike Riggs noted yesterday, the U.S. Court of Appeals for the 7th Circuit upheld a warrantless search of a cellphone belonging to a suspected meth supplier who had just been arrested. The search in this case was limited to finding the phone's number, which police then used to subpoena the suspect's call history. Writing for the Court, Judge Richard Posner deemed this "a minimally invasive  search" justified by the possibility that the defendant's confederates, learning of his arrest, might attempt to remotely erase the data on his phone. (The two main justifications for allowing a "search incident to arrest" without a warrant are preserving evidence and protecting officers from hidden weapons.) Posner likened obtaining the phone's number to opening an arrestee's diary "to verify his  name and address":

If police are entitled to open a pocket diary to copy the owner's address, they should be  entitled to turn on a cell phone to  learn its number. If allowed to leaf through a pocket address book, as they are, they should be entitled to read the address book in a cell phone. If forbidden to peruse love letters recognized as such found wedged between the pages of the address book, they should be forbidden to read love letters in the files of a cell phone.

At the same time, Posner acknowledged that smartphones are essentially computers, providing a wealth of private information. In this case the government argued that a cellphone is a "container," noting that "a container found on the person of someone who is arrested may be searched as an incident to the arrest even if the arresting officers don't suspect that the container holds a weapon or  contraband." Posner's response:

A modern cell phone is in one aspect a diary writ large. Even when used primarily for business it is quite likely to contain, or  provide ready access  to, a vast body of personal data. The potential invasion of privacy in a search of a cell phone is greater than in a search of a "container" in a conventional sense even when the conventional container is a purse that contains an address book (itself a container) and photos. Judges are becoming aware that a computer (and remember that a modern cellphone is a computer) is not just another purse or address book….An iPhone application called iCam allows you to access your home computer's webcam so that you can survey the inside of your home while you'rea thousand miles away….At the touch of a button a cell phone search becomes a house search, and that is not a search of a "container" in any normal sense of that word, though a house contains data.

In this case, Posner added, "we are quite a distance from the use of the iCam to view what is happening in the bedroom of the owner of the seized cell phone":

We said it was conceivable, not probable,  that a confederate of the defendant would have wiped the data from the defendant's cell phone before the government could obtain a search warrant; and it could be argued that the risk of destruction of evidence was indeed so slight as to be outweighed by  the invasion of privacy from the search. But the "invasion," limited as it was to the cell phone's number, was also slight. 

The cellphone search in this case was less invasive than the one upheld by the California Supreme Court last year, which involved reading a suspected MDMA dealer's text messages. That decision prompted the state legislature to pass a law requiring a warrant for cellphone searches. Although the vote was nearly unanimous, reflecting the widespread sentiment that a cellphone's contents are highly personal, Gov. Jerry Brown vetoed the bill, saying the courts should decide these issues. But if the remote possibility of remote wiping can justify looking through a cellphone without a warrant for evidence of an arrestee's alleged crime, the courts may have a hard time drawing a line between reasonable and unreasonable searches in this context.

If police bust a guy for making meth, can they peruse his text messages (as in the California case) to see if he has set up any deals? Can they open the web browser on his phone to see if he has been looking up synthesis instructions? Can they open every text file, just in case it contains an ingredient list? Can they look at his photos, in case he has proudly taken a picture of his garage lab? And remember: Any rule that applies to a smartphone will apply to all sorts of portable computers. This seems like a situation where a clear statutory rule is preferable to the continuing uncertainty of case-by-case adjudication.

NEXT: Who Needs a Warrant? Florida Cop Dresses As Power Company Repairman to Gain Access to Home

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  1. I think that the reasoning is sound. I just don’t see the police limiting themselves to those restrictions. If the courts stuck to that line it would be fine. But again, I don’t seem them doing so.

    1. What activities beyond these restrictions do you foresee the police doing?

      1. If I can get the number off your phone, what if I just happen to see something while getting it? And to get the number, I have to go into the settings and open various menus. Well, if we are letting the police do that, why not let them open other menus? Do you really have an expectation of privacy then?

        That is where this always leads. It never leads to less police power.

        1. Pretty much exactly this.

          Whoops I accidentally clicked on the number and saw there recent text message conversation, these new fangled touch screens sure are sensitive aren’t they?

          Sometimes that will be how it happens, sometimes it will just be how they put it in their report. How will we be able to tell the difference? Is a judge really going to throw out that evidence?

          That doesn’t even get into the cops snooping into your private stuff just for shits n’ giggles.

          1. And once finding stuff in “plain sight” becomes common, it is very easy for courts to then rule that you don’t have any expectation of privacy in your phone. You know they are going to look to get your phone number. And you know that will involve them seeing things on your phone. How can you expect it to be private then?

            It never happens in just one case. It happens over years in several cases.

    2. That is the problem isn’t it? I can’t really see how getting your cellphone isn’t analogous to looking in a diary. Yet, where does the bootstrapping end?

      I don’t see why they need the number to get the subpoena. We have the guy’s name. We can subpoena the phone records based on his name and carrier. The carrier’s name is usually on the phone.

      So why go here? Why let them get the number when there are other ways of doing it?

      1. Exactly. This is the thin end of the wedge.

      2. Posner is very good and I like judges trying to apply the law to new technology like this but at a certain point the technology is different enough to warrant extra precautions to protect our rights not less.

        1. I usually like him. He is a great legal writer. The best since Holmes or Hand. But I think he is wrong here.

        2. Posner is pretty good? Perhaps you haven’t heard of his belief in a living, breathing constitution, and his expressed belief that the document, being old, no longer has much application in the real world.


      3. If it’s prepaid the name may be fake.

    3. “‘I think that the reasoning is sound. ”

      How so? Surely if they were concerned about remote tampering, they could have just removed the battery. Wouldn’t even get them to court, I imagine.

  2. Don’t bring a record of your crime to the place where you’re committing a crime. It ain’t hard.

    Another piece of advice: don’t put anything on your (non password protected) cellphone that you don’t want the world to see. Forget about police searches; what if it gets lost or stolen?

    1. You’re assuming the police never make a mistake and arrest innocent people?

    2. The court this woman to turn over an unencrypted version of her computer hard drive, in lieu of typing in her encryption password for them. It seems we’re on a trajectory where self-incrimination will be compelled.

      1. Self incrimination- and a restriction on the use of one’s own private property. That’s discovery/retention laws for you.

      2. That’s a court issue. If you don’t trust the courts then requiring a warrant is not that important, is it?

    3. Don’t bring a record of your crime to the place where you’re committing a crime. It ain’t hard.

      *cough*innocent until proven guilty*cough*

    4. I just think any argument that a cell phone, computer, etc. is not part of a person’s “papers and effects” is absurd. It is the modern equivalent of an address book, diary and box of saved letters. Get a fucking warrant.

    5. Cmon tulpa that’s riduculous, “guilty because he was arrested.”

  3. I still have a feature phone (a dumb phone). This is one of the contributing reasons why I don’t have a smart phone, and why I am reluctant to buy an eReader.

    1. Uh…why are you afraid of an eReader?

      1. Well, they can already search the library records to see that you once checked out a book that might have helped you commit crime. Imagine the fun they could have with a “forensic analysis” of the thousand books you have on your eReader.

        1. Or they see you were reading legalization literature and you had a bottle of Visine in your pocket- PARAPHERNALIA! SEARCH HIS HOUSE!

        2. The cops would see my Reason Hit&Run; RSS widget on the main screen of my phone, and my ass would get disappeared.

    2. Smart phones and tablets can be password locked. You can also encrypt all the personal data on them with a password that is effectively unhackable. Finally, I’ll bet there are apps that let you quickly and easily erase everything on your smart phone if the need should arise.

      1. If I should every have a real need to get a smart phone, I will definitely invest the time and effort to protect it.

        1. My “smart” phone has no data service enabled. It doesn’t even inform me what weather I am experiencing.

          1. Get your ass outside. No data plan required.

  4. “”…the defendant’s confederates, learning of his arrest, might attempt to remotely erase the data on his phone…”

    1. How can some erase data on someone else’s phone.

    2. The call records are maintained the the phone company. These are necessary for billing purposes.

    This judge is in over his head technologically.

    1. And even if you could remotely erase the information, the police getting the number off the phone wouldn’t stop you.

    2. 1. How can some erase data on someone else’s phone.

      I have avast mobile on my phone. It is set up so that if it gets lost or stolen I can go online and have avast lock down the phone so that the GPS is permanently on and erase all the data. Any moderately clever drug dealer could have the passwords for that shared with someone else to do this when the police get the phone.

      1. True. But how does the cops getting the number prevent this?

        1. I think it’s possible to remotely delete any record of a phone’s number. So when the officers come back, warrant in hand, they find the phone completely factory reset, with no phone number attached to it.

          1. Ah. Is it bad that I increasingly find myself rooting for the criminals in these things? It is a subconscious thing. When you mention your scenario, my heart just naturally kind of jumps at the thought of the cops finding nothing. Cops have really fucked up people’s respect for the law.

          2. The phone companies can track what numbers have been on the phone by ESN.

  5. “If police are entitled to open a pocket diary to copy the owner’s address”

    I dispute this. It is a search of personal items.

    1. Agreed. If the Judge is correct that the police have the right to do this “limited” search on a diary, wouldn’t they also have the same right to search a wallet to get a credit card number to be later used to access records from the credit card company.

      1. Why stop there? The person has already been arrested, so their stuff can be searched, right? It is logically consistent to then say that their vehicle, house, workplace, or anything they own can then be searched without a warrant.

        Unfortunately, it is compelling to search and confiscate any “weapon” from an arrestee. Taking away items should be sufficient to verify safety, tampering with them is unnecessary and should require a warrant.

        If someone is arrested for, say, flashing, I don’t see why the cops would have to search any “container” even though it is removed from the person’s possession. If they see what looks like weed in a translucent film canister, investigating further is one thing (although weed shouldn’t be illegal in the first place). Looking in an opaque black film canister “because there could be weed in it” is irrelevant to charging someone with flashing.

        1. If you’re arrested, the police are going to have to handle everything you have on you anyway when they put you in jail. So forbidding them to look through it is silly.

          That’s not true of your house or your car.

          1. They don’t have to look through shit. If it becomes long term storage, the only issue is perishables and things like batteries. Just seal it up in a paper bag and that’s that.

      2. They do, if you’re arrested.

    2. Search incident to arrest. Your personal items you’re carrying are not protected. Deal.

      If the arrest is under false pretenses you can sue, and in any case any evidence obtained will be inadmissible.

      1. “Search incident to arrest.”

        The concept is a load of shit.

  6. I seem to recall an earlier ruling that said if your phone wasn’t pasword protected, the cops were free to rifle through it upon your arrest. That was the day I password locked my phone. If they can’t open it*, they can’t access it.

    *yes, I’m fully aware that any smartphone can be broken with appropriate devices and software, but the arresting officer (currently, anyway) isn’t going to have that in the patrol car.

    1. Apparently, the iPhone 4/4s is damned tough to crack if you don’t use just the 4 digit PIN.

  7. As an electrical engineer, I’d also point out that if you have possession of a mobile device, you can prevent anyone from remotely accessing the device by removing the battery. Or you can place it in a Faraday cage. (Otherwise known as a grounded metal box.) The device cannot be remotely accessed while within the enclosure because it attenuates the radio signal.

    1. I have seen one of those cages at a retailer’s lab. They used it to test TVs and shit.

  8. So if I put a label on the outside of my phone with the phone number on it, can they still snoop into my phone?

    1. Or if you just tell them?

      1. Yeah, I was assuming I’d be unconscious in the ambulance or sobbing of my dog’s corpse at the time.

  9. “If police bust a guy for making meth . . . ”

    It’s only a pre-libertarian jurisprudence discussion until THAT power/circumstance can be seriously challenged and debated.

  10. I think I’d be ok with a rule saying that the phone really is a container, yet anything that requires a network connection is off-limits and subject to the exclusionary principle.

    From a technical perspective I can deal with that – just configure the phone not to store anything locally.

    1. If you password protect anything it requires a warrant (or your permission) to access.

  11. It’s not about the evidence the cops find and use with disclosure. It’s about the evidence they find and don’t disclose, but follow up on anyway.

    If a cop has a right to know the # of a phone without a warrant, they can get it by using it to dial another #. They don’t need to open a single menu, but we all know they will and soon, we’ll be talking about “should a cop be entitled to whatever they find on a phone since it uses publicly-regulated bandwidth to send signals.

    Slippery slope, people.

    1. So the cops are allowed to make calls using my phone, just not look up the phone number? That’s wacky.

      I’d rather they not make calls using my phone, thanks.

      1. I’d rather they not use any of my property or effects for any reason whatsoever without getting a warrant first.

        1. Is what’s yours yours or property of the State/Tribe/Govt?

  12. Yeah these stupid cops are really starting to get annoying, I mean seriously.

  13. I think law enforcement should be required to obtain a search warrant before searching a suspect’s or arrestee’s cell phone.

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