The issue of drunk driving is one of those highly politicized topics that appeals to a cross-section of conservatives and leftists because it promises both a revival of the temperance movement and an avenue for the growth of state controls. Aside from these political implications, the issue of drunk driving provides insight into a more general question of political philosophy. The essential question is: under what conditions, if any, can the state legitimately outlaw certain forms of behavior that pose a risk to others?
Before addressing this issue, it is necessary to establish certain prerequisites. I will distinguish “drunk driving” from “drinking and driving” or “driving while drinking.” While drunk driving is the act of driving while intoxicated, drinking and driving is act of consuming some quantity of alcohol, but not necessarily being intoxicated. Likewise, driving while consuming alcohol does not necessarily imply intoxication. I will define “intoxicated” to mean “an alcohol level sufficiently high to pose a significantly increased risk to others while driving.”
Furthermore, I will presume that the only legitimate function of the state is to prevent and punish the initiation of force. Since neither drinking and driving nor driving while drinking as such pose a significant risk to others, I will consider it as self-evident that they should be legal. On the other hand, I will presume that drunk driving creates a significantly risk that the majority of drivers would strongly want to avoid.
Since the provision of roads is not a legitimate function of the state, this issue is complicated…