After reaching a peak during the 1990s, death sentences and executions havedeclined throughout the states. During this time, a steady stream of states havetaken the step to join a growing group of abolitionist states, or alternatively, have a moratorium on executions in place. In a parallel development, supportfor the death penalty among the U.S. population has equally waned. However,the trend towards a shrinking death penalty is not without its challenges. The ultimate punishment is still administered in some states, and legislation aiming to maintain the use of the death penalty continue to be proposed and enacted in state legislatures. Previous research provides a wide range of reasons explaining the current situation at state level. This compilation thesis argues that state legislatures, a hitherto less researched area in this context, play a central role in recent developments. With a lack of research on determinants for death penalty legislation, meaning both legislation that aims to limit the use ofthe death penalty and that which aims to maintain or expand it, a significant gap exists in the literature and subsequently our understanding of a declining death penalty. This thesis attempts to address this gap by contributing with fourstudies of a unique set of death penalty legislation in 38 states covering the years 1999-2018. The papers examine legislative activity in terms of both billproposals and enacted legislation, as well as the role of women legislators andthat of governors and their use of vetoes targeting death penalty legislation. Party and institutional aspects are shown to matter to the current development, but with a number of caveats depending on the type of bill and with greatdiversity between different state legislatures and their shaping of death penalty policy.