Skip to main content

Spillover Effects of Permissive Marijuana Laws — Lessons from Local Alcohol and Firearms Controls

Posted by on Tuesday, October 31, 2017 in News.

All recreational marijuana states give local governments the power to ban the commercial distribution of the drug. Even some medical marijuana states do the same. The appeal of such “marijuana localism” is plain: It arguably gives communities that oppose legalization the ability to “opt-out” of legalization and thereby defuses some opposition to state reforms.

A couple of years ago, however, I wrote a lengthy article (Marijuana Localism) that makes the case against local control over marijuana. (The article is excerpted on pages 561-68 of the book.) One of the key points I make is that local control over marijuana can be illusory and potentially even harmful (at least from the perspective of the broader society). Part of the problem stems from the fact that marijuana is so readily transportable. This undermines many of the restrictions local governments seek to impose on the distribution of the drug (e.g., special local taxes). Worse yet, to the extent local restrictions actually prove effective, they might simply displace certain harms (e.g., drugged driving) onto more permissive jurisdictions nearby.

The nation has a long experience with local alcohol controls, so I mined the social science research on the effects of those controls to test my hypotheses. In so doing, I reached some very sobering conclusions. Namely, the “research on local alcohol control suggests that local alcohol regulations often have effects outside of the communities that adopt them,” ultimately suggesting that “the state or even the national government might be better suited to control . . . marijuana.”

Local alcohol controls provides one nice case study, but there are other possibilities to consider. A new report (here from fivethirtyeight examines one of them: state firearms controls. The authors of the report examined the effect of state firearms regulations on the flow of crime-involved firearms across state lines. In particular, they analyzed the flow of such firearms between 107 pairs of neighboring states, each of which was ranked (from 1-50) according to the relative strictness of its firearms regulations. While the authors found that firearms tended to move from more permissive states to more restrictive ones, their conclusions were tentative:

“[T]he relationship between gun laws and firearm recoveries generally appears to be more pronounced in states with larger differences in the strictness of their gun laws. [For example,] Illinois and Indiana are 28.5 points apart in our . . . gun rankings, and in 2016, for every 100,000 residents of the two states combined, Illinois recovered nearly 6.5 more firearms originating in Indiana than Indiana recovered guns originating in Illinois. . . .”

“Overall, the relationship between the two factors is decent but not extremely strong, and plenty of neighbor pairs have large differences in the strictness of their gun laws but only a small differential in the relative size of their gun trade. Vermont, for example, has far looser gun laws than Massachusetts and New York, but the gun trade between Vermont and each of those two neighbors is fairly even. . . .”

“The available evidence does, however, show that gun laws in one state seem to affect their neighbors, which makes this an important area of study in efforts to better understand the flow of firearms used in crimes.”

The authors suggest more work needs to be done. It will be interesting to follow the research on firearms, and to consider what other objects of local control (e.g., tobacco) might lend some insights for debates over local control of marijuana as well.