This chapter critically evaluates how experiments are used to study cognitive processes involved in legal reasoning. Looking at research on legal presumptions, heuristic processing, and various types of bias in judicial decision-making, the analysis considers how experiments with judges, lay participants, and other legally trained populations have contributed to our understanding of the psychological processes involved in fact-finding and legal decision-making. It explores how behavioral economics, dual process models, cultural cognition, and motivated reasoning frameworks have been used to inform experimental research. The chapter concludes with a discussion of what findings add to our normative understanding of issues like accuracy and neutrality in decision-making and a call to better integrate knowledge gained through experimental methods across disciplinary boundaries.