The United States relies on life sentences and virtual life sentences much more than other countries, and the reliance on these long term and permanent sentences has been increasing despite a general decline in violent crime. In this thesis, I evaluate a hypothetical proposal to cap all prison terms at 15 years in California. I estimate the effects of such a proposal on both crime and costs for the state, and I also offer anecdotal evidence to capture how such a proposal would affect the lives of individuals who are formerly incarcerated. I estimate that the three-year recidivism rate of those who would be released under a 15-year cap would be 26% and that the state would see increased spending via social services and parole costs but increased savings via prison closures. The savings would outweigh the costs, with an estimated net savings of $13-18 billion in total accrued 15 years after the policy is implemented. Finally, I recommend that this policy change would be improved if it was paired with increased spending on rehabilitation and reentry services.