After being randomly assigned to receive policy effectiveness information expressed as attributable benefit, attributable risk, or relative risk, 318 graduate students were asked to indicate their preferences for the current voluntary seat belt use policy, a mandatory seat belt policy, or mandatory passive restraints. A control group received no data. Exposure to effectiveness information (any type) was significantly associated with favoring either mandatory seat belts or passive restraints over the current policy. Those exposed to attributable benefit or risk data were more apt to make proregulatory choices than subjects exposed to relative risk data. Attitudes toward government regulation and specific views about personal freedom and policy effectiveness were also found to be significant predictors of policy preference.