You Know That Mobile Phone Tracking Data You Used As Evidence In Over 10,000 Court Cases? Turns Out Some Of It Was Wrong, But We're Not Sure Which Yet

from the sorry-about-that dept

As many have pointed out, our mobile phones are the perfect surveillance device. Most people carry them around -- voluntarily -- while they are awake. Put this together with the fact that mobile phones have to connect to a nearby transmitter in order to work, and you end up with a pretty good idea of where the person using the device is throughout the day. No surprise, then, that police and prosecutors around the world turn routinely to phone tracking data when they are investigating cases. But as the New York Times reports, there can be serious problems with simply assuming the results are reliable. The Danish authorities have to review over 10,000 court verdicts because of errors in mobile phone tracking data that was offered as evidence in those cases. In addition, Denmark's director of public prosecutions has ordered a two-month halt in the use of this location data in criminal cases while experts try to sort out the problems:

The first error was found in an I.T. system that converts phone companies' raw data into evidence that the police and prosecutors can use to place a person at the scene of a crime. During the conversions, the system omitted some data, creating a less-detailed image of a cellphone’s whereabouts. The error was fixed in March after the national police discovered it.

In a second problem, some cellphone tracking data linked phones to the wrong cellphone towers, potentially connecting innocent people to crime scenes, said Jan Reckendorff, the director of public prosecutions.

It's not clear yet how serious these blunders will turn out to be -- it might only be a few, relatively minor cases. Or it might involve a large number of more serious crimes. Either way, it's a salutary reminder that however useful a technology might appear for the purposes of solving crimes -- and however straightforward its application seems -- things can and will go wrong. There's another approach that some people tend to view as infallible: the use of DNA sequencing techniques to identify suspects from material left at the scene of the crime. DNA is undoubtedly a powerful way of pulling information from tiny amounts of material, but there are a number of ways in which it can mislead badly. The same applies to mobile phone location data, as the Danish experience usefully underlines.

Follow me @glynmoody on Twitter, Diaspora, or Mastodon.

Hide this

Thank you for reading this Techdirt post. With so many things competing for everyone’s attention these days, we really appreciate you giving us your time. We work hard every day to put quality content out there for our community.

Techdirt is one of the few remaining truly independent media outlets. We do not have a giant corporation behind us, and we rely heavily on our community to support us, in an age when advertisers are increasingly uninterested in sponsoring small, independent sites — especially a site like ours that is unwilling to pull punches in its reporting and analysis.

While other websites have resorted to paywalls, registration requirements, and increasingly annoying/intrusive advertising, we have always kept Techdirt open and available to anyone. But in order to continue doing so, we need your support. We offer a variety of ways for our readers to support us, from direct donations to special subscriptions and cool merchandise — and every little bit helps. Thank you.

–The Techdirt Team

Filed Under: denmark, evidence, lawsuits, location data, tracking data

Reader Comments

Subscribe: RSS

View by: Time | Thread

  1. icon
    Ole Husgaard (profile), 30 Aug 2019 @ 3:17pm

    Some information from a local

    I live in Denmark and have followed this case closely.

    The problem is that telecoms are required by law to collect location data of phones. This law has been declared illegal (violation of human rights and the proportionality principle) by the EU court of justice several years ago, but has not been changed yet.

    The location data is frequently used in criminal cases here, and counts as objective evidence, like a vitness report.

    This scandal is that our police "converted" the data obtained from the telecom before presenting it to the court, and that there were several serious errors in this "conversion". Even worse, our police kept this secret for months after it was discovered.

    Now add that the defense in a criminal case in our country are not allowed to do any investigation, as our police has a monopoly on this. So if a defence lawyer tries to obtain the original location data from the telecom he would break the law and loose his license to practise law.

    This means that the defense in a criminal case has to rely on the location data "evidence" presented to the court by the prosecution.

    When news of the "conversion errors" were first made public, we were told that this error could have been happening since 2012, but later it has been revealed that it could have happened even before that.

    More than half of all "criminals" in jail in my country today vere convicted because of this faulty location data presented to the courts, so this is a huge scandal.

Add Your Comment

Have a Techdirt Account? Sign in now. Want one? Register here

Subscribe to the Techdirt Daily newsletter

Comment Options:

  • Use markdown. Use plain text.
  • Remember name/email/url (set a cookie)

Follow Techdirt
Special Affiliate Offer

Report this ad  |  Hide Techdirt ads
Essential Reading
Techdirt Deals
Report this ad  |  Hide Techdirt ads
Techdirt Insider Chat
Report this ad  |  Hide Techdirt ads
Recent Stories
Report this ad  |  Hide Techdirt ads

This site, like most other sites on the web, uses cookies. For more information, see our privacy policy. Got it

Email This

This feature is only available to registered users. Register or sign in to use it.