He has conducted research on how jurors make legal decisions in criminal and civil cases. He is particularly interested in how legal and extralegal factors affect jurors' legal judgments. He became interested in the jury system newly introduced in South Korea and conducted an empirical study with his Korean colleagues to examine jury competence as indicated by judge-jury agreement in actual jury trials. He has recently published a book in Korea, The jury system and legal psychology (2010). As a social psychologist, he is also interested in stereotyping and prejudice, implicit bias, and social judgment.