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The Law Blogger is a law-related blog that informs and discusses current matters of legal interest to readers of The Oakland Press and to consumers of legal services in the community. We hope readers will  find it entertaining but also informative. The Law Blogger does not, however, impart legal advice, as only attorneys are licensed to provide legal counsel.
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Sunday, April 28, 2019

Geofence Warrants and Privacy Rights

Geofence warrants, also known as reverse location warrants, are new to the law enforcement toolbox. Now these warrants are quickly becoming recognized by law enforcement as an effective method to gathering evidence of crime.

In some cases, evidence gathered by multi-step reverse location warrants is the only evidence available in the case. These warrants are also getting attention from the national media and soon could be heading to the SCOTUS for a show-down with our privacy rights and the Fourth Amendment's probable cause requirement.

What is a Geofence Warrant?

In recent years, police, investigating a crime with few or no clues, have increasingly turned to almighty Google to help them find the perpetrator. First, law enforcement issues a warrant to Google requesting data about any and all devices present within certain spatial and temporal parameters matching an unsolved crime.

Google then responds to the multi-step warrant by transmitting to the requesting agency a log designating -anonymously- all registered devices that fit the warrant's parameters. Law enforcement then takes that anonymous raw data and determines which code-designated devices merit further information. These suspect devices then become the subject of a second warrant to Google; more personal and identifying information is requested. [Note: the SCOTUS has already held that law enforcement must first obtain a search warrant pursuant to the Fourth Amendment prior to forcing access to a suspect's password protected cell phone.]

After providing lip service to their policy of narrowly construing such warrant requests, Google responds by tapping into its Sensorvault database, created in 2009. Sensorvault is connected to Google's "Location History" service, as well as other location-based apps such as the Web & App Activity; a separate database.

We've all noticed when our iPhones or Android devices prompt us to enable the location history function. This allows Google to provide you with directions to anywhere in the world along with many other spatially-related information services.

The first-known Geofence warrant was issued in 2017 in North Carolina. The case related to the suspected arson of a 7-story apartment complex. Raleigh Police had no leads to bolster their suspicions; for a year, their investigation bore no fruit until they requested a warrant for information from Google.

Often, judges issue such warrants under seal to protect the privacy of the many users having nothing to do with the crime being investigated. The Raleigh Police, for example, have made reverse location warrant requests in murder and sexual assault cases in addition to the arson suspect.

Google now processes hundreds of such multi-step warrants weekly; that number is expected to rise significantly as law enforcement agencies become aware of this new investigative practice. You don't have to be a tech genius to realize the significance of such warrants for law enforcement.

One of the drawbacks to securing such warrants are the significant processing delays. The multi-step reverse location warrant requests have become so numerous, Google has a separate division dealing exclusively with such requests. 8-weeks to six-month delays are not uncommon; there are also two components to the request.

Geofence Warrants Provide Circumstantial Evidence of Crime.

Law enforcement has been securing location data from a specific suspect’s or witness’ digital devices for over a decade. Reverse location warrants, however, constitute a relatively new digital dragnet for when a case has gone cold, or has no viable clues.

This new multi-step warrant process is much more comprehensive than a cell tower data dump. For decades, police and prosecutors have been using data pulled from cell phone towers to solve crimes. 

Data from cell towers is limited and incomplete relative to the Sensorvault and Web & Activity App databases. For example, Google's data is ultra-precise and historically detailed, even when a suspect or witness does not place a call on their cell. In other words, Google's data depicts every aspect of our lives, not just the patterns elicited when actual calls are placed.

Such comprehensive information about suspects and witnesses constitute a veritable treasure trove of circumstantial evidence for law enforcement. Digital location tracking of a specific Android or iPhone device can produce circumstantial evidence of a suspect’s relationship to an unsolved crime. 

In every criminal jury trial here in Michigan, circumstantial evidence is commonly defined as: 

  • Facts can be proved by direct evidence from a witness or an exhibit. Direct evidence is evidence about what we actually see or hear. For example, if you look outside and see rain falling, that is direct evidence that it is raining.
  • Facts can also be proved by indirect, or circumstantialevidenceCircumstantial evidence is evidence that normally or reasonably leads to other facts. So, for example, if you see a person come in from outside wearing a raincoat covered with small drops of water, that would be circumstantial evidence that it is raining.
  • You may consider circumstantial evidenceCircumstantial evidence by itself, or a combination of circumstantial evidence and direct evidence, can be used to prove the elements of a crime. In other words, you should consider all the evidence that you believe.

Judges always instruct juries that an accused can be convicted solely on the basis of circumstantial evidence. Direct evidence tends to be higher-quality evidence, but circumstantial evidence is often sufficient to convict the accused.

There are no known cases, however, where a suspect has been charged solely on the basis of a geofence warrant. An independent criminal investigation must still be conducted using the reverse location data. 

Over time, however, a case based solely on circumstantial evidence cultivated from a geofence warrant is sure to present itself to the court's. In the proper judicial and appellate hands, a sensible policy can be fashioned going forward. At present, privacy concerns, relative to the law enforcement process -as envisioned by the drafters of the 4th Amendment- is at risk

Geofence Warrants Raise Privacy Concerns.

There can be many legitimate –non-criminal- reasons for an individual’s presence within the parameters of a reverse location warrant. In fact, usually, all but one device has a legitimate and potentially relevant reason for leaving a particular digital footprint.

Sensorvault and the Web & Activity App contains an enormous amount of our personal data. The database contains detailed historic records of our locations -both temporal and virtual- the products we use, the products we view, the identities of our friends, and it can match-up times associated with each of these and many other minutia of our daily lives. This, of course, raises significant privacy concerns.
Sometimes, however, law enforcement simply gets it wrong. This was the case for Jorge Molina who was mistakenly charged with murder in Phoenix, Arizona a few months ago. Mr. Molina’s case was recently profiled in the New York Times.

Turns out, Molina’s mother’s boyfriend used his vehicle on occasion. So while the reverse location warrant yielded some eventual fruit for law enforcement, it disrupted Mr. Molina’s life first by violating his privacy and precipitating a week-long incarceration.

Once you are identified as a witness or suspect, turning-off your Location History, opting out, or deleting the history can also be viewed as circumstantial evidence of guilt. Such acts can be held against a suspect, just as wiping a hard drive clean is often used against an accused. Covering your tracks constitutes circumstantial evidence of guilt; or at least it will be portrayed as such by the prosecutor.

Are Multi-Step Reverse Location Warrants Constitutional?

The Fourth Amendment to the United States Constitution states that, "no warrants shall issue, but upon probable cause, supported by oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized."  One concern with multi-step reverse location warrants is their wide spatial temporal breadth. 

Particularity is required under the Fourth Amendment, which calls for a limited search based on probable cause. Most geofence warrants, on the other hand, by their nature, seek raw data covering potentially thousands of individuals over a wide-span of time. 

In addition, the two-step warrant process scoops-up scores of innocent bystanders within its dragnet. Courts usually abhor the fishing-expedition technique for issuing warrants for the main reason that fishing expeditions are not based on probable cause.

Multi-step reverse location warrants can also be technical in nature. A neutral magistrate or judge, as well as law enforcement personnel, defer to Big Data technicians to properly tailor such warrant requests and the raw data resulting from the requests. 

The NYT examined initial warrants used the first-step of the geofence warrant process. Those warrants merely sited the fact that: a) most Americans have cell phones; and b) Google possessed location data for many of those phones.

Geofence Warrants Will Become A Pervasive Law Enforcement Technique.

Reverse location warrants are becoming a well-known jackpot among federal and state criminal investigators. In addition to the increased requests, it will not take long for law enforcement to overreach, placing the process squarely before the appellate courts, on its way to the SCOTUS.

Last year’s series of bombings around Austin, Texas presented a perfect opportunity to utilize geofence warrants. A series of geofence warrants for each bomb site would yield raw anonymous data pertaining to devices around those specific bombing locations at or about the time-frame of the explosions.

This data could then be mined for patterns of activity and for the presence of a common device appearing in several locations. Federal investigators could then bring the resources of the United States to bear on identifying the patterns or the commonly present devices.

This, of course, presumes that the bomber would be simple enough to have a geo-tracking device on his or her possession when committing these crimes. These days, however, try getting off the data grid. Data is collected when your phone is turned-off; when your vehicle is turned on; and with your every key-stroke tracked.

Even if a suspect does not carry a geo-tracking device, or has an older model vehicle not wired to the Internet, the presence of potential witnesses also can be identified. Some witnesses may not even realize they were near the scene of a crime until confronted by law enforcement investigators.

We here at the Law Blogger don't see these warrant requests going away anytime soon. Nor do we anticipate Google changing its stated policy of only providing information they are required by law to provide.

We Can Help.

Our criminal defense and appellate practices have provided us with decades of experience in such matters. If you or a family member are the subject of such a warrant request, or have intersected with law enforcement in any way, give us a call to discuss your options.
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