The key to targeted killing is surveillance and verification.

This element of counterinsurgency warfare looks for clear targets and makes sure that the people found are the same people that intelligence points to. This style of conflict is also one reason drones have so dominated the popular understanding of America’s long-running war. Now, this idea is also the impetus behind a Pentagon program called “Jetson,” which can identify unique biometric signatures from heartbeats using a laser.

The device, as reported by MIT Technology Review, detects a person’s “unique cardiac signature with an infrared laser” at up to 650 feet away from the person in question, with longer ranges possible in the future.

That kind of range is impressive, and it can work through light clothing, though it’s likely stopped by heavier garments and, one would imagine, body armor. This is because the laser reads vibrations on the surface of the person. A special gimbal holds the beam in focus so the laser can, over 30 seconds, identify a unique signature.

As the MIT Technology Review noted, finding a unique signature in a database first requires those databases, and so a collection of biometric information is a first step before using a laser to confirm a person is who the sensor says they are. In countries where the U.S. military regularly collects biometric information, that’s one way for the military to build the database, though there are also plenty of other avenues for people to volunteer information, like heartbeats, to commercial tracking services.

Asymmetric warfare has a long tradition of uniformed forces trying new approaches to distinguish between civilians and irregular combatants. Should biometric targeting become a regular part of this future, the laws of war will likely need to explicitly address the questions facing data processing broadly: can the model account for false positives? Does living in an occupied country invalidate a claim to the privacy of one’s own heartbeat? Can the data be maliciously spoofed, leading to failure at the point of the data set that might be imperceptible to users?

Jetson was built at the request of U.S. Special Forces and fits into a broader set of tools for quietly executing the assigned tasks of long-running war. It will likely, within the parameters it was designed for, help fulfill those existing objectives. It is not hard to imagine the technology finding a home with internal security forces, where the conditions and legalities are different. Jetson is, after all, adapted from a commercial vibration-reading tool, and could likely be incorporated into a range of sensor packages as an additional feature.

Kelsey Atherton blogs about military technology for C4ISRNET, Fifth Domain, Defense News, and Military Times. He previously wrote for Popular Science, and also created, solicited, and edited content for a group blog on political science fiction and international security.

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