Goal

This study will (1) provide Mississippi Department of Public Safety (Commercial Transportation Enforcement Division and Motor Carrier Safety Division) with lidar-based tools measuring headway gap and (2) examine and report the extent to which the use of these devices improves safety outcomes related to following too closely violations. The project will also examine the effect of the same devices on speeding violation and crash frequencies.

Summary

State partners in a few jurisdictions (e.g., Georgia) have implemented lidar-based tools for objectively measuring and recording following distance for commercial motor vehicles. Baseline data appears to suggest that the implementation of this technology has outsized impacts on the rate at which following-too-closely violations are enforced. However, the last (and only) time USDOT performed research on the topic was over a quarter-century ago. 

A lidar device will be provided to each commercial vehicle enforcement official for each shift worked. Using a quasi-experimental study design, this project will assess whether implementing the lidar-based tool affects outcomes related to following too closely (e.g., violation frequency, crash frequency, etc.). 

This project will result in a report describing the rates of following too closely violations and rear-end crashes involving commercial motor vehicles before and after the widespread implementation of lidar-based enforcement tools across the entire state of Mississippi.

Impacts

By evaluating lidar-based enforcement tools, this project aims to improve safety outcomes.