Abstract: The unprecedented concentration of the mentally ill in United States' jails and prisons has gained much attention in the past few decades, however little research has examined mental illness as a risk factor for offending. The current study utilizes a survey consisting of quantitative and qualitative items to assess different variables among the inmates at Boulder County Jail (BCJ). The current study intended to address this gap in the extant literature, and assessed for demographics, mental health diagnoses and services, parental incarceration and mental illness, substance use, offending histories, and victimization histories. The findings support extant research on the concentration of the mentally ill in jails, along with their disproportionate rate of parental incarceration and mental health problems, victimization, and high number of incarcerations. The current study also puts forth tentative relationships between specific mental health diagnoses, parental factors, and types of victimization as a child and adult, and how they are subsequently related to offending. Finally, the findings from this study provide areas for future research that could help disentangle the complicated relationships between mental illness and offending. 3 ACKNOWLEDGMENTS I would first and foremost like to thank my thesis chair and mentor, Dr. Joanne Belknap, for her continual work, advice, and support throughout the past year. She continually encouraged me to go above and beyond what I thought I could accomplish with both my honors thesis and undergraduate career. Dr. Belknap worked tirelessly for months to get this study approved by the Institutional Review Board (IRB) and the Boulder County Jail (BCJ), and once approved, she coached me through the data collection and analysis, along with any other assistance that I asked for. I will forever be grateful to Dr. Belknap for helping me realize my passion for research with the inmate population and for reaffirming my goal to pursue a doctoral degree in Criminology. I would also like to thank my committee members, Dr. Radelet and Dr. Dimidijian for their support and encouragement throughout this process. I will never forget this experience, and I thank you for being a part of it. I would also like to thank the inmates of BCJ who were kind enough to participate in my study. Many inmates at the BCJ shared some highly personal and sensitive experiences, and I extremely grateful for their participation. I would also like to thank Sergeant Lydia Mitchell at BCJ, who has worked with us throughout …