Accident Potential was a feature in an early version of Watch Dogs.
This feature was a HUD element shown by the ctOS when looking at a car being driven. It showed the probability of the driver causing an accident. Distracted drivers might have a bigger Accident Potential, just as aware drivers may have a lower one. Speed is also a factor that influenced Accident Potential.
The HUD was first shown during the gameplay video at E3 2012, but was scrapped in development.