1. A computer-implemented system for determining vehicle occupancy, comprising: light beam pulses emitted from a lidar system to a vehicle passing by the lidar system; a scanner to generate scans of an object from the light beam pulses, each scan comprising: a signal receipt module to receive a signal from each of the beam pulses reflected at a point of reflection along a segment of the passing vehicle; a time module to measure a time from when each beam pulse was emitted from the lidar system to receipt of the signal; a distance module to calculate a distance of the signal from the lidar system using the measured time; a position module to position the points of reflection for that vehicle segment in relation to one another as a scan; a compiler to compile the scans in a consecutive order according to the vehicle and generating a three-dimensional image of an interior of the vehicle from the consecutive scans; and an occupancy determination module to determine at least one of a presence and absence of vehicle occupancy based on the three-dimensional image.