Across California, local psychiatric inpatient treatment capacity has declined significantly; counties have dramatically expanded jail capacity; and state prisons have been forced to alter their use of solitary confinement because of a landmark settlement. In this dissertation, I study the impacts of these important events and trends. I use quantitative methods and rich data assembled from a variety of public but infrequently examined sources.

First, I study the consequences of losing inpatient psychiatric treatment capacity on both jail incarceration and the prevalence of mental illness among the jail incarcerated. I use multilevel models and a quasi-experimental synthetic control group research design. I find that a county losing all local psychiatric treatment capacity leads to higher rates of jail bookings and significantly increased prevalence of mental illness in jail.

Second, I examine the impact of jail expansion on jail incarceration and overcrowding using a difference-in-difference research design. I find that additional jail capacity causes increased jail bookings, total average daily population (ADP), and misdemeanor ADP but decreased early releases. The effect of additional jail capacity grows larger over time the longer the jail expansion is open, and the effect varies substantially between counties.

Third, I investigate how solitary confinement use evolves in response to legal challenges and how solitary confinement use impacts rates of violence in prisons. I document that the landmark case Ashker v. Governor of California led to a meaningful reduction in solitary confinement use, but that the practice has persisted and is still frequently used by prisons. Additionally, I find that solitary confinement use is not associated with the safety of prisoners but may be weakly associated with rates of recorded violence against prison staff.