Costly missed connections: Visitation and misconduct in California prisons.

Social isolation is a major public health crisis with particularly deleterious consequences for vulnerable populations including incarcerated people. Theoretically, visitation from family should reduce social isolation and improve outcomes among incarcerated people, but existing quasi-experimental research provides limited support for the relationship between visitation and in-custody outcomes. We revisit the effect of visitation on in-custody misconduct-an important but administratively defined measure of institutional safety-by exploiting the fact that fluctuations in gasoline prices create unanticipated shifts in visitation uncorrelated with other factors associated with misconduct. We combine this quasi-experimental variation with smartphone mobility data identifying prison visits from cell phone pings and administrative data on misconduct in California prisons. We find that increases in visits induced by changes in transportation costs are negatively related to misconduct (particularly use-of-force events and personal battery), with effects concentrated immediately after visitation. Although the policy implications are subtle, these findings suggest that some strategies that reduce visitation barriers could be cost-effective ways to reduce prison violence. More broadly, they suggest that social connections have causal repercussions for violence and safety in extreme institutional environments.