Sibyl Algorithm

A biomechatronic network that judges every citizen's criminal potential.

The Sibyl System is the powerful biomechatronic computer network that governs Japan in the Psycho-Pass universe. It continually monitors the psychological traits of Japanese citizens using a "cymatic scan," producing a psychometric assessment called a Psycho-Pass. This assessment includes a numeric Crime Coefficient index, revealing the citizen's criminality potential, and a color-coded Hue, alerting law enforcement to other data. When a targeted individual's Crime Coefficient index exceeds the accepted threshold of 100, they are pursued, apprehended, and either arrested or killed by field officers of the Crime Investigation Department of the Ministry of Welfare's Public Safety Bureau.

Quick Facts

Nature: a powerful biomechatronic computer network
Key component: Dominator weapons
First appearance: Psycho-Pass Season 1

Lore & Background

The Sibyl System is not a single artificial intelligence but a powerful biomechatronic computer network. It governs Japan by continually scanning the mental states of every passing citizen. Elite officers known as Inspectors research and evaluate crime scenes with the assistance of Enforcers, who are latent criminals charged with protecting the Inspectors and carrying out their instructions. Both are equipped with personally activated hand-held weapons called Dominators, whose integrated scanners provide the target's immediate Psycho-Pass.

The gun-like weapon can only fire when approved by the Sibyl System and triggered by its owner. Inspectors have jurisdiction to fire their Dominators on the Enforcers should they pose a danger to the public or the Inspectors themselves. The system's most notable anomaly is the Criminally Asymptomatic individual—a person persistently assessed by the Sibyl System as having a low crime coefficient despite all actions and attitudes, thus protecting them from Dominator harm.

Shogo Makishima is one such individual, and he is invited by Joshu Kasei, the android form of Sibyl, to join their ranks. He refuses and flees.

Reader's Guide

The Sibyl Algorithm functions by using a "cymatic scan" to continually monitor the psychological traits of Japanese citizens. The resulting psychometric assessment is called a Psycho-Pass, which includes a numeric Crime Coefficient index. When this index exceeds the accepted threshold of 100, the individual is pursued, apprehended, and either arrested or killed. The primary enforcement tool is the Dominator, a hand-held weapon whose integrated scanner provides the target's immediate Psycho-Pass.

The weapon can only fire when approved by the Sibyl System and triggered by its owner. However, the system has a critical limitation: Criminally Asymptomatic individuals, like Shogo Makishima, are persistently assessed as having a low crime coefficient despite all actions and attitudes, making them immune to Dominator harm. This reveals that the system cannot judge those who commit crimes without a corresponding psychological profile.