The Volokh Conspiracy

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Yes, Warrants Allow a Search Through the Whole Phone

A comment on a mistaken way to limit computer searches— focusing on People v. Carson from the Michigan Court of Appeals.


As regular readers know, one of the big issues in computer search and seizure law that I often write about is how to limit computer warrant searches.  If everything needs to be searched to find the evidence, and information outside the scope of the evidence sought can be used in plain view, doesn't a search of a computer with a warrant result in a general search — the kind that the Fourth Amendment was enacted to prevent.  My own answer to this puzzle is that the Fourth Amendment requires use restrictions for digital searches.  The whole computer can be searched, but evidence outside the scope of the warrant cannot be used.

In the last year or two, however, a few state courts have tried to limit computer searches through novel interpretations of the particularity requirement. I think this is wrong, and I thought I would explain why.

Consider a recent example from the Michigan Court of Appeals, People v. Carson.  In Carson, the government obtained a search warrant to search a cell phone seized incident to arrest as required by Riley v. California. The government had arrested Carson for working with his girlfriend to steal $70,000 in cash from his neighbor's safe.  The government then obtained a warrant to search the phone for "records or documents pertaining to the investigation of Larceny in a Building and Safe Breaking."  The officers searched the phone and found text messages between Carson and his girlfriend in which they discuss the crime.  The text messages were then used at trial to help prove the crime.

The Michigan Court of Appeals ruled in Carson that the warrant had a blatant Fourth Amendment defect—an error so egregious, in fact, that Carson's conviction must be overturned even though his lawyer never even challenged the warrant at trial.  According to the court, Carson's conviction must be overturned because his lawyer was ineffective by failing to challenge the warrant, as if the lawyer had made that motion, the warrant would have been deemed unconstitutional and the evidence suppressed as the good faith exception would not apply to such an obvious mistake.

What, then, was the obvious mistake?  According to the court, the warrant allowed a search through the entire phone for the evidence sought.  This was plainly wrong, the court reasoned, because the warrant should have been limited to the specific apps and file types that the agents had specific reason to believe would have the evidence sought:

[I]t would have been wholly appropriate to issue a warrant authorizing the police to engage in a search of the phone's contents limited in scope to correspondence between these two regarding the crimes; this would include SMS messages, internet-based messaging applications such as Messenger or SnapChat, direct messages sent through social media platforms such as Instagram or Twitter, emails, and other similar applications. The warrant that was actually issued placed no limitations on the scope of the search and authorized the police to search everything, specifically mentioning photographs and videos. Authorization for a search of defendant's photographs and videos, despite there being no evidence suggesting that these files would yield anything relevant, is particularly troubling in light of the tendency of people in our modern world to store compromising photographs and videos of themselves with romantic partners on their mobile devices. Moreover, people usually can directly access file storage systems such as Dropbox and Google Drive directly from their phones, creating a whole new realm of personal information that the police was given free license to peruse. The pandemic also saw the emergence of applications such as "BetterHelp" and "Talkspace" through which people can have text message-based sessions with their psychotherapists, and applications such as "MyChart" allow mobile storage of detailed medical records as well as private conversations between patients and doctors. Simply put, this warrant authorized precisely the form "wide-ranging exploratory searches the framers intended to prohibit." Hughes, 506 Mich at 539 (quotation marks and citation omitted). Indeed, there are likely many people who would view an unfettered search of the contents of their mobile device as more deeply violative of their privacy than the sort of general search of a home that the framers originally intended to avoid.

According to the court, any decent lawyer would haver realized that this was an egregious mistake, so much that the good-faith exception would not apply and the lawyer was ineffective for not litigating the issue.

But the error belongs to the Michigan Court of Appeals, it seems to me, not to the defense counsel. This is the same mistake that the initial Fifth Circuit panel made in United States v. Morton before the en banc court upheld the search under the good faith exception and declined to address the issue on the merits.   As I blogged in 2021, in response to Morton,

The place where the phone is located—or maybe the phone itself—is the place to be searched.  And you have probable cause to believe the evidence is in the phone. That's all the government needs, I think.  It doesn't make sense to limit the government's search within the place to be searched to particular forms of evidence any more than it makes sense to limit the search of tax records in a house to  "documents stored on 8.5 X 11 paper" or "items in boxes designed to store records." As the Supreme Court stressed in Ross v. United States, "[w]hen a legitimate search is under way, and when its purpose and its limits have been precisely defined, nice distinctions between closets, drawers, and containers . . .  must give way to the interest in the prompt and efficient completion of the task at hand." Everything in the place to be searched can be searched.

I certainly get the Carson court's concern. It's the right concern. It's just the wrong way to address it.  The animating idea is to limit what can be seized in plain view by only allowing the government to look in a few particular places in the digital device where evidence is most likely to be stored.  If the government is only allowed to search in a few places, the thinking runs, they won't see overly much.  And as a result, only so much can come into plain view.

That's why the Carson court is concerned with people having compromising pictures on their phone and apps with communications with therapists. The court is worried about a cost/benefit balance of allowing a search through that stuff: If a search through it is allowed, then the government can use that, disclose it, post it on the Internet, and do lots of other terrible stuff outside the law enforcement mission.  That would be bad.  And as I have argued before, there's a straightforward answer to that concern: The Fourth Amendment should impose a use restriction on non-responsive data in the digital setting.

But not letting the government look through particular kinds of files makes no sense. You don't know in advance where digital evidence of a crime is going to be.  Some apps or file types may be more likely to yield evidence than other apps or file types, but you can't rule them out.  Take Carson's concerns with looking through photographs. Based on news stories and cases, it seems to be common for those who steal things to take pictures of what they steal, storing pictures of the loot on their phone. In a case about stolen goods, why should the government be forbidden to search through the photos on a phone to look for that evidence?

It is  true, of course, that Riley requires a warrant.  But once the government has probable cause and gets a warrant, they should be allowed to search through the entire phone for the evidence based on the warrant just like they can search through an entire house.  If the government gets a warrant to search a home for a knife used in a murder, the warrant won't limit the search to the knife drawer in the kitchen just because a judge thinks that this is where knives usually go.  The knife might be in the knife drawer, sure.  But it could be in a cupboard, or in the bedroom closet, or underneath a floorboard.  The warrant should let the government search there, too.  The answer is use restrictions, not arbitrary limits on where the government can look.

The Carson court also raises a concern with accessing cloud-stored contents from the phone, but that seems obviously different: A search of the cloud from a phone is a search of the cloud, not a search of the phone.  As always, stay tuned.