Fifth Amendment

If You Want to Keep Your Phone Contents Secret, Perhaps Don't Use a Fingerprint Lock

Unlike passcodes, judges seem willing to force cooperation with authorities for access.


Credit: CPOA / photo on flickr

Your fingerprints are both information that identifies who you are and can be used as evidence from crime scenes. They are also, now, cybersecurity tools that allow you to lock away information from snoops, be they hackers or government agents.

While citizens have the right to avoid self-incrimination, prosecutors are legally permitted as part of the investigation of a crime to do things like collect your fingerprints and DNA samples, with a court order. That information may nevertheless incriminate you if it's attached to a crime scene.

Now that fingerprints can be used to secure smartphones, they can be used to get a whole lot more information about the person other than confirming his or her identity. So can a citizen be forced to use his or her own fingerprint to provide access to information that could be more incriminating than just their physical location? Is sticking your finger on a phone an act that should be treated the same as punching in your passcode?

For the latter, prosecutors have had a difficult time attempting to force citizens to give up their codes because it would potentially be incriminatory compelled speech. Thus we have the foundation for the current iteration of the encryption fight to try to force tech companies like Apple help law enforcement bypass their own security.

But for the fingerprints, so far judges seem to be more inclined to treat it like an order to provide a house key or essentially the way they've been treating fingerprints thus far. In two cases, judges have ordered citizens to use their fingers to open a phone to let investigators review the content.

It's a complicated issue for legal experts. The Los Angeles Times spoke to a couple of them:

Even with the limited outlines of the inquiry, [law Professor Susan] Brenner said the act of compelling a person in custody to press her finger against a phone breached the 5th Amendment's protection against self-incrimination. It forced Bkchadzhyan to testify —without uttering a word — because by moving her finger and unlocking the phone, she authenticated its contents.

"By showing you opened the phone, you showed that you have control over it," Brenner said. "It's the same as if she went home and pulled out paper documents — she's produced it."

But Albert Gidari, the director of privacy at Stanford Law School's Center for Internet and Society, said the action might not violate the 5th Amendment prohibition of self-incrimination.

"Unlike disclosing passcodes, you are not compelled to speak or say what's 'in your mind' to law enforcement," Gidari said. "'Put your finger here' is not testimonial or self-incriminating."

But consider this idea: The government can get a warrant to search your home. If you refuse to cooperate, they can force their way in. Citizens can passively resist a search warrant of a physical location (or actively resist and get themselves arrested), but it doesn't stop police from carrying out the search. This is not remotely the same situation, and treating it as though a fingerprint is just another type of "key" is ignoring the issue that the police can't simply force the matter when the suspect refuses to cooperate.

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  1. If they type, let it be. If they swipe, that’s the key!

    1. As creepy guy in the van by the school likes to say: It’s touching time.

      1. It’s not the worst of the five senses a creep can use, you know.

    2. If you want to keep your PM lynx, perhaps don’t rely on boozy Reason staffers.

  2. If the government has a search warrant, they can search your home, but if they come across a safe, they can’t force you to unlock it, can they? Why should it be any different for a phone? If they have a search warrant, and your phone isn’t secured, they can access it, if it is, they should have to find another means of access. They would call in a professional safe cracker for your house, sounds like they need to hire someone to crack the phone’s lock.

    1. They can force you to unlock it or pry the thing open if you don’t. That is assuming that the warrant covered the safe.

      1. The SCOTUS might say differently if it is a combination safe:…..afes/3343/

    2. If the government has a search warrant, they can search your home, but if they come across a safe, they can’t force you to unlock it, can they?

      Pretty sure they can, actually. They don’t need to, because there are people who will open it for them.

      Phones, though, can’t be cracked by the local PD as easily as a safe. So its you, or (practically speaking) nobody.

      1. I don’t think they should ban encryption. But if you refuse to give up the key and the government has a warrant, they should be able to throw you in jail for contempt if you won’t comply.

        1. you have a 5A right against self-incrimination

        2. I disagree. I do not believe you should have to provide *any* assistance to investigators.

          You may not, assuming they have a proper warrant, *interfere* with them. But you should not have to assist them in any way. To do so, IMO, violates your 5th amendment rights – at the very least the spirit of the 5th amendment.

          Of course, if they have proper permission to search, they have permission to access in any way necessary. So if you don’t want your front door knocked off its hinges you may wish to consider some limited assistance. But it should not be compellable.

        3. Why? Why should someone be forced to assist the government in gathering evidence that would incriminate themselves? There’s probably a bunch of bullshit lawyer logic they use to try to argue that it isn’t a violation of the fifth amendment, but it clearly is.

          There seems to be a number of people who think that if some restriction upon the government’s power would make the government’s job more difficult to carry out, then that restriction should vanish. In other words, our rights should vanish when it is convenient for the government. I don’t think so. I would rather some bad people get away than allow that to happen, and that is completely in line with how our system is actually supposed to work.

          Can’t catch some Bad Guy without violating the constitution? Too bad.

      2. The question is really about encryption; one can forget about the computer/phone/safelock part entirely. There must be some precedent in case law for the authori-tays wanting cipher to encrypted old-fashioned letters from a suspect.

  3. Well if you don’t have something to hide.

    /what most Americans actually think

    1. “Sure, give me your phone and the unlock code.”

      That generally produces incoherent spluttering, but shuts them the fuck up.

    2. If you don’t have something to hide, then you probably don’t have anything worth showing.

      /what I think

  4. It’s a complicated issue for legal experts “experts”.


  5. Fingerprints make for terrible security anyway. It’s a password that can never be changed.

    1. So much this.

      Plus, the scanners tend to be shit. Why swipe my fucking finger ten times when I can bang out a six-character unlock code in half the time?

      1. Our time clocks at work are fingerprint-based. Pretty much everybody hates them.

      2. seriously, i was at my kid cousin’s house and his fingerprint unlocked my phone

    2. Plus the fact that your fingerprints are all over the phone.

    1. You try cobbling together enough Trump links when the polls haven’t even closed yet.

      1. It’s over. Trump is going to be the GOP nominee, and Hillary will be President.

        1. Nah. As things currently stand, Trump beats Hillary.

          A lot of ground still to cover, of course.

          1. Including the indictment.

            1. You’re referring to Corey Lewandowsk, right? ‘Cause Hillary will never see the inside of a courtroom.

          2. The only scenario I can see where Trump _might_ beat her is if she gets indicted post-convention. Which of course ain’t gonna happen thanks to Obama, Lynch, and the overclassification excuse.

            1. Which is too bad, because it’s not classification that’s the problem. It’s the fact that she intentionally hid her State Dept communication from FOIA requests. The fact that she got caught and tepidly handed some over after the fact, doesn’t change the circs.

              1. She turned federal records law on its head, from records belonging to the feds to a theory of records belonging to her, wherein she holds the discretion of what her employer gets to see. Total entitled royalty behavior.

                But Obama will start campaigning for her, and will come up with all sorts of excuses. The media will play its expected role of bootlickers as always.

              2. … because it’s not classification that’s the problem.

                Diane (Paul),

                I suggest that a significant number of Secretary Clinton’s would-be prosecutors in the U.S. Congress are are approximately as corrupt and jealous of their positions as she is, and are concerned that they might be exposed for their own maleficence during any trial/inquest which they subject her to.

                It also seems to me that ordinary voters are inundated with pabulum sufficient to encourage them to vote along party lines (or not vote at all).

            2. I do not think she’s going to come across well in the debates.

              1. I agree… but who’s going to be on stage with her? The comparison will be relative, and she will win.

                As usual, this will again be the most important election in a generation, and every Bolshevik Leftist will vote for her ignoring all of her flaws including her Iraq war vote.

              2. I do not think she’s going to come across well in the debates.

                She’ll be carried over the line by the press. And before anyone thinks I’m shilling for Trump, I’m not, because I don’t believe Trump will beat Hillary in a debate. Especially a debate carefully crafted to ask wonky questions pointed at a former sec. of state.

                But even if he pulled a complete Justin Trudeau and surprised everyone in the debates, he’d lose even if he won.

                1. Paul,

                  Have you seen Hillary lately? There was a day when she could answer wonky questions and come across as pretty sharp. So, don’t think I am just slamming on Hillary here. But those days are long gone. Her health is terrible. She has no energy and is lucky to put together two coherent sentences. She is going to be a disaster in the debates.

                2. She’ll be carried over the line by the press.

                  If she wins, that will be one big reason why.

                  She’s a horrible campaigner. She has an off-putting personality. Her poll results rise and fall in direct opposition to how visible she is. She’s a known quantity with high negatives. Her record is a festival of oppo-ads-in-waiting. Without a Blue Wall of media protection, she’s hopeless.

                  The other reason she might win is if the Repubs actually manage to wrest control of Trump’s campaign from Trump. They’ve proven there is no advantage to big to squander.

                3. She does not do well when she’s put on the spot, and I think Trump will do his best to make her have to think on her feet, and she could easily embarrass herself. That, combined with her general unlikability, could give Trump a chance.

                  The debates are going to be highly viewed, so I don’t think the media will play as big a role as they normally do.

                  1. The other thing Crusty is that all of the media pants shitting over Trump is going to work to his advantage. The media has built him up to be this lunatic monster. The majority of the public will watch the debates and see Trump look reasonable and Presidential and wonder what all of the pants shitting was about.

                  2. She does not do well when she’s put on the spot, and I think Trump will do his best to make her have to think on her feet, and she could easily embarrass herself


                    I make a point of not watching debates, but back when I did, it seems that the other candidate doesn’t put you on the spot, it’s the media’s job to put you on the spot. They ask questions, the candidates answer. So the only question remaining is how will the debates questions be structured?

        2. I wouldn’t be so sure about Hillary beating Trump. There’s certainly a high chance, but it’s far from an inevitability.

            1. And usually candidates who accuse an entire culture of being rapists doesn’t go on to get the nomination of a major political party. Trump has pretty much blown up all past trends and expectations of pollsters, and he’s barely begun attacking Hillary.

              Hillary could still very well win, but it’s going to be close, and it’s going to be very, very messy.

              1. Its a matter of time before Hillary tries to energize her campus base by visibly supporting the “every male a rapist” line, so I suspect both candidates are going to neutralize each other on the controversial “opposition to rape” issue.

    2. Now, if they used *fingerprints* for the access password ?.

      1. *mental note for the next time my fargin’ IT department makes me change all my fargin’ passwords*

    3. They’re time-wasting like Simeone.


  6. I don’t see why this is any different than a key. The key is your thumb. The government if it has a warrant can demand your key, the fact that it is your thumb should make no difference. Also, your finger prints are not considered private. They don’t need a warrant to get them. They are a physical characteristic.

    The 4th Amendment says people’s papers and possession should be safe from unreasonable government intrusion. It does not say they should be safe from all government intrusion. Reason seems to be advocating that people should be able to put things beyond the reach of the government in all circumstances. The 4th Amendment doesn’t say that. And it shouldn’t say that. There are times when you should have to turn things over to the government. If reason disagrees with that, then they should be honest and say they object to warrants in general.

    1. I don’t think the point is 4th amendment against searches. It’s 5th amendment against self-incrimination

      1. The 5th Amendment protects you against testifying. It doesn’t protect you against revealing your physical characteristics.

        1. Reveal your characteristics in a court room, and you’ll probably get cited for contempt.

        2. how is that different then keeping a password secret. you can’t be forced to give up your password, which unlocks the phone, but you can be forced to give up your finger, which unlocks the phone. the end result is the same

    2. Reason doesn’t seem to be taking a strong stand one way or the other here. Just noting an interesting legal question. And giving some advice on keeping your phone secure from government searches.
      Of course phones are subject to warrants. That doesn’t mean people are obliged to make it easy for them to execute search warrants.

      1. Either you have to give them the key to the thing or you don’t. If you don’t and that makes it impossible for the cops to unlock, then you are making it out of reach of even legitimate government intrusion. Reason’s position has been consistently that that is okay.

        There is nothing wishy washy about their position at all. I don’t know why you think there is. And I strongly disagree with their position. Its very short sided and poorly thought out. Its nothing but a knee jerk reaction.

        1. I was mainly just talking about this article and this specific case. I don’t see any declaration that making you use your fingerprint is definitely a 5th amendment violation.

          I think you are right that the fingerprint is the same as a key. If they can make you turn over the key, they can make you use your finger. If on the other hand you use a strong password and you “forget” it, then they are out of luck (same if you “forget” where you put the key to your safe).

          I can remember Reason making a strong case that Apple shouldn’t have to help break their encryption (which I agree with). But I don’t recall any consistent position saying that everyone has the right to keep the contents of their phone completely hidden under any circumstances. This article certainly isn’t making such a case.

          1. It is making that case. The encryption is such that without the key you cant get into it. So if reason says you shouldn’t have to provide the key, then they are saying it should be completely hidden. They are making that case just not very openly.

        2. If the police come to my house with a warrant, that doesn’t compel me to write down the password to a desktop computer on the premises. What it does mean is that I cannot physically prevent the police from conducting a search. If I choose not to provide the password, the police are authorized to find other means of entry to the computer files.

          Tell me why a cell phone is different, and then tell me why using a biometric means of computer security is different than using a password.

          1. yes it does. If you know the pass word, they can get a court to order you to hand it over. And they should be able to. If the door to your closet was locked, they could ask you for a key. The question is do the police have a right to search the contents. If the answer is yes, you can’t then refuse to let them do so by refusing to give the password. If you think you can, then you don’t believe warrants of any kind are legitimate.

            1. And they should be able to.

              You are a very liberty-minded person, clearly.

  7. Shackford, it’s 4:34 and I don’t see any links!!!!

  8. Wherez mai Lynx?

    1. Robby’s phone is getting poor reception in the bar he’s at.

      1. Probably couldn’t find parking at the bar and had to park his Aztek a couple blocks down.

        1. Aztek – that’s cruel, but deserved under the circumstances.

          1. I wish I could claim credit, but I believe it was Fist that nailed down Robbie’s choice of personal transport.

    2. American or European?

  9. They can and will pry my fingerprint from my cold dead hands.

  10. You know they’re all sitting around the break room taking bets on how long they can delay the links before we riot.


  12. Links must be Suave’s again. He’s stuck in the bathroom. He’s having hair troubles and they had to send out an intern for more gel.

    1. Linko Suave

  13. I’m getting in a wood chipper kind of mood, here.

    1. This is Reason, big T. We make our own damned links.

      1. Hi, Injun.

    2. I’m outta here. Is there a libertarian competitor to Reason? If not, we need to bust Reason’s monopoly.

      Or we could be whiny b****es and ask the DOJ to break up Reason like AT&T.

      1. And at least AT&T hired the occasional minority.

        Amirite fellas?


      2. You can always go to

        1. Thanks – I had forgotten about that site.

        1. Thanks – I hadn’t seen that site.

  14. And I’m getting served an ad with what appears to be a female human midsection with the FUPA to end all FUPAs.

    1. Why did you make me look up FUPA? – 1 internet

      1. No force involved. 😛

        1. Suction maybe

          1. Good one.

    2. Why did you make me look up FUPA? – 1 internet

    3. Thanks a lot. Now I know what “FUPA” means.

      1. For those that don’t know, it’s the part of the muffin top that has overflowed the mold.

        1. Not quite, muffin-top is fat above the waistline which hangs over. If it’s all in the front it’s called an apron belly. FUPA is Fat Upper Pubic Area, the area above the genitals but below the waistline.

          1. I was taking some poetic license there.

    4. I always end up with pictures of Jonathan Taylor Thomas ( I think I once played him in a game of beer pong while in Boston. I made a lot of really stupid Tool Time jokes.),and McCauley Caulkin.

  15. And these people think the libertarian moment is upon us?

    I don’t think so.

    Not with this kind of disregard for PM links punctuality.

    1. If you like your punctual links, you can keep your punctual links.

    2. The sun does not rise and set on the PM links, Rufus.

      1. Merely sets. It rises on the AM links.

        Unless you’re in Australia, then the whole thing is flip-flopped.

    3. You people are sooooo needy. Yeah, I said you people.

      1. [runs sobbing from room]

  16. What if you throw it to the ground and say I ain’t part of your system.

    1. Or apply SuperGlue to your finger.

  17. At this point, the PM links are gonna be so anti-climactic, like watching porn right after sex.

    1. If you’re married, the best part is the porn after sex.

      1. I think you pissed off your partner

  18. If you are concerned at this you probably also should take consider not using your face, smart watch, fitness tracker, bluetooth devices, location, and wifi networks as means of unlocking your phone.

  19. My solution to this is not to carry around a device everywhere I go that contains everything that anyone might want to know about me. I have a brain for that and access to that is definitely protected by the 5th amendment.

    1. If you’re not breaking the law what are you concerned about?

    2. Cite? Until it’s specifically covered by case law, i wouldn’t be too sure given the copsuckers on the bench.

  20. A physical key can be forced, one way or another. As for a password, there is an old libertarian ditty, from Germany of all places:

    Die Gedanken sind frei., wer kann sie erraten…. (Our thoughts, they are free, who can can guess them….)

  21. Do the OJ thing – widen your hand so the glove don’t fit – and clumsily or by pressing too hard or swiping off-center.

    I always use the fingerprint pass – my computard friends thought it was neato back when they saw me use it in 2010.

  22. I’ve said it before and I’ll say it again. Using something that you leave behind on everything you touch to secure anything is a terrible idea.

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