The Safety Benefits Of Freeway Management Systems And Motorist Assistance Patrols

Freeway Management Systems (FMSs) and Motorist Assistance Patrols (MAPs) are two policy tools used by public officials to improve the efficiency of motor vehicle travel on urban highways. Although FMSs and MAPs were developed primarily to reduce traffic congestion, they are widely believed to improve traffic safety as well. However, despite the fact that more than 100 of these programs exist in the U.S. today (more than 50 of each kind), surprisingly little is known about the safety benefits of either FMSs or MAPs in practice. To date, public officials have little knowledge of the magnitude of the safety effects of these programs, let alone the dollar value of the resulting safety benefits. This paper provides strong empirical evidence of the safety effects of these two tools through two case-study assessments - one in Phoenix, Arizona and the other in the Twin Cities area, St. Paul/Minneapolis, Minnesota. The paper uses a fixed effects negative binomial regression model to show that both FMSs and MAPs significantly reduce multivehicle, low-severity crashes. The paper then monetizes these safety effects to show that investments in both policy tools are justified by their resulting safety benefits alone. These results both confirm the widely held belief that FMSs and MAPs improve highway safety and demonstrate that the policy tools represent sound investments of taxpayer dollars, at least in urban areas similar to Phoenix and the Twin Cities.