Public policy design proceeds by first defining a policy problem and then proposing and evaluating a set of policy alternatives for it. It is a deeply political process with no clear answers and with an outcome that often reflects the opinion of the majority in framing and solving problems. Consequently it may lead to sub-optimal policies that are not inclusive. We seek to address such problems by developing a novel computational methodology based on the creation and execution of simulation models for each alternative. Our methodology enriches these models with meta-simulation structures and processes that operationalize the assumptions behind each alternative. This is achieved by embedding such assumptions as simulation constraints at various levels throughout the design. Furthermore, our methodology evaluates alternatives in terms of explicit criteria supplied by the policy makers. Overall, this process provides insight and transparency to policy design as modeling assumptions, policy mechanics, evaluation criteria and their consequences become explicit and can be examined for every alternative. We describe Politika, a prototype of such a methodology on the web and provide appropriate examples that explain how the quality of scrutiny, debate and critique over policy can be enhanced.