Civil liberties are rights enjoyed by individuals guaranteeing them protection from the arbitrary or discriminatory acts of government. Kohlberg's cognitive-developmental theory of moral reasoning and studies of behavioral/abstract attitudinal measures provide a rationale for examining moral reasoning processes, intelligence, and selected personality and demographic variables in relations to civil liberties attitudes and to a behavioral measure of support for civil liberties. An adult college sample (N=162) was used to test hypotheses that moral reasoning scores and the specified measures of individual differences would be significantly correlated with both the behavioral (petition signing) and the attitudinal measures of civil liberties. Results indicated that the sample was moderately pro-liberatarian on both the behavioral and attitudinal measures. Partial confirmation of the hypotheses occurred; scores of moral reasoning and of intelligence correlated positively with the behavioral measures. The personality variables of authoritarianism and dogmatism correlated negatively with the civil liberties attitude score. The data offered moderate support for Kohlberg's cognitive-developmental theory of moral reasoning. (Author)