Banded

During sorting she receives a device known as 'The Band'. It's a large watch-like device that never comes off, and it measures a citizen's karma on a scale from one to one hundred. If a citizen does good, they gain points. If a citizen does bad, including breaking laws, they lose points. When your number reaches zero, the band acts as judge, jury, and executioner, and you are injected with toxins that kill you within minutes.