{"id":6141,"date":"2019-02-17T13:58:51","date_gmt":"2019-02-17T17:58:51","guid":{"rendered":"http:\/\/ncjolt.org\/?p=6141"},"modified":"2020-06-04T20:52:27","modified_gmt":"2020-06-04T20:52:27","slug":"reverse-warrants-casting-a-data-mining-net-into-a-sea-of-cell-phone-location-data-to-catch-criminals-who-commit-pattern-crimes","status":"publish","type":"post","link":"https:\/\/journals.law.unc.edu\/ncjolt\/blogs\/reverse-warrants-casting-a-data-mining-net-into-a-sea-of-cell-phone-location-data-to-catch-criminals-who-commit-pattern-crimes\/","title":{"rendered":"Reverse Warrants: Casting a Data Mining Net into a Sea of Cell Phone Location Data to Catch Criminals Who Commit Pattern Crimes"},"content":{"rendered":"\n

A reverse warrant is a tool used by law enforcement to acquire data about\nall mobile devices used within a certain geographical area, during a specified\ntime, in order to develop suspects.  They\nhave been used by the Raleigh Police department on several occasions in high\nprofile cases<\/a>, including a recent fire that was suspected for arson\nwhich destroyed a high-rise under construction and shut down several city\nblocks downtown.  The use of reverse\nwarrants has been questioned<\/a>\non the grounds of whether they contain enough particularity to satisfy the\nFourth Amendment: are they a technologically-aided fishing expedition?  No, reverse warrants are instead closer to a\nmodern pen\nregister rather than a wiretap<\/a>. \nReverse warrants do not acquire identifying information, nor the content\nof communications, and are therefore constitutional.<\/p>\n\n\n

So what is a Reverse warrant?  A\nreverse warrant demands from a technology company, such as Google<\/a>, a list of\nmobile devices that were near the scene of a crime when the crime\noccurred.  The technology that makes a\nreverse warrant possible (and a powerful tool for law enforcement) is the\nstorage of location data that smartphones collect through normal use<\/a>.  Every time a smartphone opens up Google Maps,\nutilizes the browser, updates the weather, or starts using nearly any\napplication on the phone \u2013 then the phone\u2019s precise location (longitude and\nlatitude) are logged.  A precise location\ncan be gathered through GPS, a Wi-Fi signal, over cellular data, or even\nthrough cell phone tower triangulation \u2013 and this location is \u201caccurate to the square foot<\/a>.\u201d<\/p>\n\n\n

When getting the list of devices that were in the area during the crime, investigators request that the phone or accounts be identified only by a numerical identifier. \u00a0Subsequent warrant requests would be submitted to get identifying information about people who were suspects or possible witnesses to the crime<\/a>.\u00a0 This two-step process means that investigators do not obtain identifying information for a person in the initial request sent to Google, but only after eliminating most of the phones and accounts from the returned reverse warrant data and submitting a new warrant.\u00a0 This also complies with both the Fourth Amendment and Google\u2019s internal way of processing warrants, helpfully described by the company as the \u201cWay of a Warrant<\/a>.\u201d<\/p>\n\n\n

Reverse warrants serve the public by giving law enforcement a method for helping to solve crimes, particularly ones that have a discernable pattern, and are a constitutional way of doing so.<\/p><\/blockquote>\n\n\n

Reverse warrants are especially useful when investigating pattern crimes, crimes that are committed by the same suspect over multiple days and times.\u00a0\u00a0 This is because the pattern itself narrows down the devices that were located within the search area: out of the possibly thousands of devices identified initially, far fewer would also be in the same area during the second crime, even fewer in the third, and so on.\u00a0 Because of this narrowing of suspects, in a recent investigation<\/a> into five robberies of a single store, federal agents bypassed the two-step process and requested the identifying information directly for all devices that were within the targeted area during all the specified times.<\/p>\n\n\n

\"\"<\/figure>\n\n\n

The above picture is an example of the geographic search area and time\nlimitation provided to Google in a reverse warrant in a pattern crime submitted\nby the FBI.  The center of the circle is\nthe location of a Dollar General store which was robbed multiple times, and the\nyellow circle represents the geographical area covered by the reverse warrant\nin this case.  The FBI set a radius of\n375m, thereby gathering the phone information for every device in an area\ncovering 109\nacres<\/a>.<\/p>\n\n\n

The most compelling argument that Reverse Warrants are constitutional comes from the Wake County District Attorney, who said<\/a> \u201c[w]e\u2019re not getting text messages or emails or phone calls without having to go through a different process and having additional information that might lead us to a specific individual.\u201d\u00a0 This is significant because it is the nature of the information which determines whether a legitimate expectation of privacy<\/a> has been violated.<\/p>\n\n\n

When law enforcement uses technological aids to narrow down a list of suspects using information held by Google; not identifying individuals whose devices were in the area of the crime when a crime took place, but instead anonymously identifying devices, it is a constitutional use of government power.\u00a0 Reverse warrants serve the public by giving law enforcement a method for helping to solve crimes, particularly ones that have a discernable pattern, and are a constitutional way of doing so. <\/p>\n\n\n

Alex Rutgers, 11 February 2019<\/p>\n","protected":false},"excerpt":{"rendered":"

A reverse warrant is a tool used by law enforcement to acquire data about all mobile devices used within a certain geographical area, during a specified time, in order to develop suspects.  They have been used by the Raleigh Police department on several occasions in high profile cases, including a recent fire that was suspected …<\/a><\/p>\n","protected":false},"author":1,"featured_media":5789,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[51],"tags":[],"_links":{"self":[{"href":"https:\/\/journals.law.unc.edu\/ncjolt\/wp-json\/wp\/v2\/posts\/6141"}],"collection":[{"href":"https:\/\/journals.law.unc.edu\/ncjolt\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/journals.law.unc.edu\/ncjolt\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/journals.law.unc.edu\/ncjolt\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/journals.law.unc.edu\/ncjolt\/wp-json\/wp\/v2\/comments?post=6141"}],"version-history":[{"count":1,"href":"https:\/\/journals.law.unc.edu\/ncjolt\/wp-json\/wp\/v2\/posts\/6141\/revisions"}],"predecessor-version":[{"id":6849,"href":"https:\/\/journals.law.unc.edu\/ncjolt\/wp-json\/wp\/v2\/posts\/6141\/revisions\/6849"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/journals.law.unc.edu\/ncjolt\/wp-json\/wp\/v2\/media\/5789"}],"wp:attachment":[{"href":"https:\/\/journals.law.unc.edu\/ncjolt\/wp-json\/wp\/v2\/media?parent=6141"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/journals.law.unc.edu\/ncjolt\/wp-json\/wp\/v2\/categories?post=6141"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/journals.law.unc.edu\/ncjolt\/wp-json\/wp\/v2\/tags?post=6141"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}