With the passage of Amendment 20 in 2000 and Amendment 64 in 2012, Colorado legalized the medicinal and recreational use of marijuana. Subsequently, Nebraskan law enforcement agencies in border counties have reported increases in arrests and jail admissions for marijuana-related offenses. In response, the Nebraska Legislature passed Legislative Resolution 520 to study potential increased costs incurred by criminal justice agencies in border counties.

In order to better understand how Colorado drug policy may have affected counties along the border, we compared trends in marijuana-related criminal justice activity among county agencies following the enactment of both Amendments. Border county arrests, jail admissions, and associated costs of incarceration were compared to two other county groups, those that contain Interstate I-80 as a major transportation route, and a “control group” comprised of the remaining counties in the state of Nebraska from 2000 through 2013. This analysis approximates a “natural experiment” based on the assumption that Nebraska counties that border Colorado will experience the largest impact from the legal changes in Colorado. Because Interstate 80 is the major east/west thoroughfare in Nebraska linking Colorado to the east, we assume the counties along the I-80 corridor will experience an impact that is less than that of border counties, but higher than control counties. Finally, we assume that “control counties” that are neither border counties, nor I-80 corridor counties, will be affected the least since 2000.