The study's main hypothesis was that subjects with dogmatic personalities would be sensitive to many of the issues which play important roles in criminal trials. Several other hypotheses were also examined. Study subjects were 264 men and women over age 21 and eligible for jury duty in New York City. Subjects were tested as individuals or in 32 groups of 6 subjects each. Subjects completed three questionnaires which measured dogmatism and attitudes toward punishment of criminals. In addition, subjects reviewed a trial transcript created by the experimenter in which the defendant was charged with robbery and assault. For different study groups, the transcript varied in terms of evidence of guilt or innocence, character witnesses' testimony, and prosecuting attorney's summation. Results showed that subjects with high dogmatism scores found the defendant guilty and were more certain of the defendant's guilt than were low dogmatics. In addition, high dogmatics were more certain of guilt when the defendant was portrayed as being antiauthority, while low dogmatics were unaffected by the manipulation of authority. Differences were statistically significant for groups but not for individuals. An unexpected finding was that high dogmatics were less resistant to persuasion than were low dogmatics. Results supported Rokeach's theory of dogmatism, with respect to high dogmatics and also showed that many aspects of a trial are interrelated and cannot be studied individually. Results suggested that attorneys' presentations should vary according to jury composition. A list of 87 references, tables, and appendixes presenting study instruments and additional results are included.