IMSI Catchers

“If law enforcement already knows the IMSI number of a specific phone and person they are trying to locate, they can program that IMSI number into the [IMSI-catcher] and it will tell them if that phone is nearby.” The Intercept

About: An IMSI-catcher (IMSI stands for International Mobile Subscriber Identity also known as “Stingrays”) is a surveillance tool secretly used by law enforcement agencies to monitor phones. This technology can be used to track who attends political demonstrations or public events. It allows whoever is using it, to access – and even edit – your calls and messages.

How does it work? IMSI-catchers are devices that act like fake cell towers, tricking phones to connect to them and enabling them to take a record of all phones in the area. When a phone connects to the fake phone tower, the IMSI number is revealed and the police can find out a person’s identity, and access and record all the device’s communications. This way all of the target’s communications go through the IMSI-catcher and can be collected, read and listened to.

Why is this wrong? IMSI catchers are intrusive surveillance tools whose use remains unregulated. They are often deployed in secret, without a clear legal basis, and without safeguards and oversight mechanisms. Their use infringes the right to privacy, freedom of expression, and freedom of assembly and association.

More info at:

Privacy International | IMSI Catchers

Privacy International | IMSI Catchers Analysis (pdf)

The Intercept | How Cops Can Secretly Track Your Phone