The effect of substance use Certificate‐of‐Need laws on access to substance use disorder treatment facilities

We investigate how substance use Certificate‐of‐Need (CON) laws influence access to substance use disorder treatment facilities in the United States. We use the National Directory of Drug and Alcohol Abuse Treatment Facilities data set, which lists all federal, state, and local government facilities and private facilities that provide substance use treatment services in 2020. Based on the locations of these facilities, we develop a novel access index to substance use disorder treatment facilities that accounts for driving distance and duration to measure the ease of reaching these facilities for individuals living at the population‐weighted county centroids. We find that counties in states with CON laws that border counties without such laws have nearly 10% less spatial accessibility to substance use disorder treatment facilities at a 5% level of significance.