Are police keyword warrants a privacy threat?

What is a keyword warrant?

A keyword warrant is a request made by a law enforcement agency to an online search service provider to identify users who searched for specific phrases or names on its search engine. These keywords are usually associated with crimes or investigation procedures (e.g., victims’ names, crime location addresses, crime methods, etc.). However, they can also be less specific.

The term is mainly associated with Google after the tech giant provided such data to law enforcement officers on several occasions. It stands pretty close to geofence warrants — cases where the police ask Google for information on persons who were close to a crime scene at a certain time.

Cases of keyword warrant

Here are a few known cases of keyword warrant requests:

• While investigating a kidnapping and sexual assault case in 2019, Wisconsin’s federal police investigators asked Google to provide them with information on all users who searched for the victim’s and her mother’s name and address.
• In 2020, the police asked for details of users who searched for the address of an arson victim.
• During the investigation of the Austin bombings that resulted in the deaths of two persons, the police looked for data on less specific keywords such as “pipe bomb” or “low explosives.”

Risks

While those methods can indeed help to catch criminals or stop criminal activity, they also introduce certain risks:

• Violation of privacy. Keyword monitoring is a pretty grave intrusion into one’s private online space. And, while we applaud the police for doing everything they can to protect us, this method can quickly go off the rails.
• Targeting innocent users. Not all the keywords are specific and can be pretty broad (e.g., a crime method), so law enforcement may falsely target people looking them up without ill intentions. Moreover, one’s device could be used by someone else who might damage their keyword reputation.

Other cases of police intervention

Keyword warrant requests are part of an ongoing trend of new police surveillance methods. Here are a few other cases:

• Clearview AI, a company providing facial recognition services by scraping users’ photos found online, provides its services to various law enforcement agencies.
• In 2018, the Australian police and the FBI initiated the biggest stings in modern history by creating a fake encrypted messaging app with installed backdoors. It led to around 800 arrests all across the globe.
• Law enforcement institutions have recently started using such innovative data-gathering tools as SmartNet or Kaseware, which allow for large-scale web scraping and raise many privacy concerns.