May 16, 2023

Countless smartphones seized in arrests and searches by police forces across the United States are being auctioned online without first having the data on them erased, a practice that can lead to crime victims being re-victimized, a new study found. In response, the largest online marketplace for items seized in U.S. law enforcement investigations says it now ensures that all phones sold through its platform will be data-wiped prior to auction.

Researchers at the University of Maryland last year purchased 228 smartphones sold “as-is” from, which bills itself as the largest auction house for police departments in the United States. Of phones they won at auction (at an average of $18 per phone), the researchers found 49 had no PIN or passcode; they were able to guess an additional 11 of the PINs by using the top-40 most popular PIN or swipe patterns.

Phones may end up in police custody for any number of reasons — such as its owner was involved in identity theft — and in these cases the phone itself was used as a tool to commit the crime.

“We initially expected that police would never auction these phones, as they would enable the buyer to recommit the same crimes as the previous owner,” the researchers explained in a paper released this month. “Unfortunately, that expectation has proven false in practice.”

The researchers said while they could have employed more aggressive technological measures to work out more of the PINs for the remaining phones they bought, they concluded based on the sample that a great many of the devices they won at auction had probably not been data-wiped and were protected only by a PIN.

Beyond what you would expect from unwiped second hand phones — every text message, picture, email, browser history, location history, etc. — the 61 phones they were able to access also contained significant amounts of data pertaining to crime — including victims’ data — the researchers found.

Some readers may be wondering at this point, “Why should we care about what happens to a criminal’s phone?” First off, it’s not entirely clear how these phones ended up for sale on PropertyRoom.

“Some folks are like, ‘Yeah, whatever, these are criminal phones,’ but are they?” said Dave Levin, an assistant professor of computer science at University of Maryland.

“We started looking at state laws around what they’re supposed to do with lost or stolen property, and we found that most of it ends up going the same route as civil asset forfeiture,” Levin continued. “Meaning, if they can’t find out who owns something, it eventually becomes the property of the state and gets shipped out to these resellers.”

Also, the researchers found that many of the phones clearly had personal information on them regarding previous or intended targets of crime: A dozen of the phones had photographs of government-issued IDs. Three of those were on phones that apparently belonged to sex workers; their phones contained communications with clients.

An overview of the phone functionality and data accessibility for phones purchased by the researchers.

One phone had full credit files for eight different people on it. On another device they found a screenshot including 11 stolen credit cards that were apparently purchased from an online carding shop. On yet another, the former owner had apparently been active in a Telegram group chat that sold tutorials on how to run identity theft scams.

The most interesting phone from the batches they bought at auction was one with a sticky note attached that included the device’s PIN and the notation “Gry Keyed,” no doubt a reference to the Graykey software that is often used by law enforcement agencies to brute-force a mobile device PIN.

“That one had the PIN on the back,” Levin said. “The message chain on that phone had 24 Experian and TransUnion credit histories”.

The University of Maryland team said they took care in their research not to further the victimization of people whose information was on the devices they purchased from That involved ensuring that none of the devices could connect to the Internet when powered on, and scanning all images on the devices against known hashes for child sexual abuse material.

It is common to find phones and other electronics for sale on auction platforms like eBay that have not been wiped of sensitive data, but in those cases eBay doesn’t possess the items being sold. In contrast, platforms like PropertyRoom obtain devices and resell them at auction directly.

PropertyRoom did not respond to multiple requests for comment. But the researchers said sometime in the past few months PropertyRoom began posting a notice stating that all mobile devices would be wiped of their data before being sold at auction.

“We informed them of our research in October 2022, and they responded that they would review our findings internally,” Levin said. “They stopped selling them for a while, but then it slowly came back, and then we made sure we won every auction. And all of the ones we got from that were indeed wiped, except there were four devices that had external SD [storage] cards in them that weren’t wiped.”

A copy of the University of Maryland study is here (PDF).

11 thoughts on “Re-Victimization from Police-Auctioned Cell Phones

  1. Mobile Me

    The Propertyroom (aka site was one of my favorites for obtaining items for play and/or resale. I’ve gotten MDTs (mobile data terminals) and Toughbooks pulled from squad cars; ID printers, DVD duplicators and more from them. I once purchased some used desktops advertised as drives being pulled (which is/was common). One of the PCs had an unconnected drive installed. I found emails, spreadsheets and Word docs containing info on security and budgeting for the Port Authority of NY/NJ (some of the docs were encrypted). It appeared that the PC belonged to a very “Big Suit” (a name I still remember). This was a year or two after “9/11”. Via email, and on a subsequent visit to their Farmingdale location for a pickup I told them what I found. Their response was that in the future they would open up the units to make sure no drives are installed. They did not seem at all concerned about what I found, nor asked what I did with the data (DOD wiped and machine was installed at a non-profit)

  2. Wannabe techguy

    “We initially expected that police would never auction these phones, as they would enable the buyer to recommit the same crimes as the previous owner,” the researchers explained in a paper released this month. “Unfortunately, that expectation has proven false in practice.”
    No offence intended, but this is very naive.

    1. Patrick

      Never trust the cops to do their jobs (or in general, honestly)

  3. Gannon

    I bought a lot of ‘surplus’ hardware from Property Room. I got what I paid for and used what I got. Kudos to the University of Maryland for pointing out the ‘Lost & Found’ Property Room was slow to see.

    On another same old of the same type …
    I saw a story about ID Theft yesterday. It was well documented, with 1/2 million taken over years. The victims were suing banks for recovery. What stood out to me was the ease with which the scammers incorporated “new” data points. Where did the banks get the idea their business methods were sound ? Hint: search AI + Large Language Models (LLM) and it will be very hard to find any “institutional” criticism or warnings.

  4. G.Scott H.

    In days before smartphones and computers, such information would have been stored on papers possibly in filing cabinets. Would filing cabinets have been auctioned to the general public with there contents? These devices would be better destroyed to protect the information.

    I have multiple times obtained machines with sensitive information still accessible. Fortunately, for the owners of that information, I immediately properly wipe the media. In the situation this article covers, the owners have no option of making sure the info is wiped. The custodians of those devices have the responsibility of ensuring the information is wiped.

  5. Tjuan

    No a police should not have access to that they rape they doc and. Civilians and play the proud boy with out the budget.

  6. Mahhn

    These devices should be destroyed not sold. It verges on malicious while standing on a ledge of stupidity to sell/give away other peoples unwiped devices.
    The time to pick up and wipe most used phones is more than their resale value.
    If a person wants to risk their own data, that’s their business. When people, companies and governments expose other peoples data, that’s a crime.

    1. Stratocaster

      Agree that there is alarming negligence there. A more altruistic approach would be to donate them to a NGO in a developing nation, if they can be reliably cleaned. I’m betting a good portion of them are burner phones because criminals.

  7. YagiElement

    Poor departmental procedures. Where I’m at, all electronic devices containing data that were evidence/property are destroyed. Cell phones and hard drives are escorted to a shred facility where the are observed being ground into fine particles. Government owned equipment has the drive or media removed if applicable. Anything with embedded memory has the data wiped or shredded depending on the devices role.

    Simple to implement a policy, but I guess either stupidity or the almighty dollar prevailed.

  8. Louise

    Cool article! Also, routers. I haven’t read the whole article, but this quote from Daily Mail:
    “Recently, researchers bought 18 used routers and found more than half contained confidential and sensitive intel from the businesses that once used them.”
    – The one surprising tech device you MUST replace after a breakup or divorce – or your ex could spy on you

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