Justice and Due Process

Geofences Aren’t the Only Reverse Warrants

What is a reverse search warrant?

Reverse search warrants are requests made by law enforcement to a technology company seeking caches of data that could be relevant to a criminal investigation.

In the case of geofence warrants, law enforcement officers request all user data within a specific location from technology companies like Google or T-Mobile. However, geofence data represents only one type of factual information that can be obtained from consumers, stored in one location, and later “mined” for information relevant to an ongoing criminal investigation.

A murder investigation in Denver, Colorado, underscores this reality. After an arson led to the death of five people, law enforcement used a reverse keyword warrant to obtain data from Google’s search history. This “warrant” suffered from the same overly broad defects of geofence searches.

In this case, officers suspected the criminal searched for the address of the victims. After obtaining data from Google through the execution of the search warrant, police arrested three defendants for the crimes committed. 

One of the defendants has challenged the constitutionality of the warrant on the grounds that it violates the Fourth Amendment because the search is too broad. Rather than gathering information about an individual suspected of committing a crime, reverse search warrants require companies to hand over troves of data to law enforcement. Once this data is obtained, agents then search for information that could lead them to a suspect.

Although this is the first legal challenge to the validity of reverse keyword searches, the constitutionality of geofence warrants has been contested by courts in Illinois, Kansas, and Virginia.

Challenges to the legal validity of these warrants touch on constitutional concerns fundamental to the existence of a free people. Reverse search warrants are the modern day equivalent of the general warrants—writs of assistance—despised by the authors of our Constitution.

It is hard to overstate the privacy implications of making reverse search warrants normative. Location data and keyword searches are only the tip of the iceberg when it comes to information stored in large digital databases. 

If police have the legal ability to search through any American’s location data or keyword searches to find information relevant to a criminal investigation, why should reverse search warrants be limited? 

In reality, no such limitation would exist, effectively stripping Americans of Fourth Amendment protections and hammering the final nail into the coffin of privacy rights. 

To prevent the continued erosion of civil rights, judges must reject these “warrants,” and state legislative chambers should pass laws ensuring that a defendant who appears before the wrong judge is not denied fundamental rights on which our constitutional order rests.