Comprehension of moral reasoning is important both for successful moral education and for Kohlbergian claims that moral reasoning development is cognitive in nature. Because a psychometrically appropriate moral comprehension instrument does not appear to exist, the Moral Comprehension Questionnaire (MCQ) was constructed in Study 1 and displayed some positive reliability and validity findings. Study 2 used this questionnaire to examine whether the increased Defining Issue Test (DIT) p scores shown by liberals is indicative of increased cognitive development. While liberals displayed slightly greater moral comprehension than conservatives, moral comprehension and political orientation mostly appear to contribute independently to high p scores. Additionally, consistent with Kohlbergian theory, comprehension of Stage 5 moral reasoning is more challenging than comprehension of Stage 3 or 4 reasoning. Consequently, while p scores are somewhat cognitive developmental in nature, they also are independently predicted by political orientation.