Information processing device and information processing system

An information processing device comprises a controller configured to execute: acquiring respective vehicle-mounted videos including an identical road section from a first vehicle that is an automated driving vehicle and a second vehicle that is a manual driving vehicle; identifying a first running trajectory corresponding to the first vehicle and a second running trajectory corresponding to the second vehicle on the basis of the vehicle-mounted videos; and making a judgment on a subject present at a first point that is a point with a divergence above a predetermined value between the first running trajectory and the second running trajectory.