Much of Peter DeScioli's research focuses on moral condemnation, especially the functions of third party judgment, moralistic punishment, and moral impartiality. Another area of his research program examines the functions of friendship by looking at how people distribute loyalties across close friends (friend ranking) and how people obscure their loyalties (rank masking). He is also investigating the psychological foundations of property and ownership by using a virtual environment to observe resource disputes in the laboratory.