My research focuses on the psychological nature of ethical decision making. I'm interested in both the cognitive and social processes involved. For example, how do individuals justify their solutions to ethical dilemmas, and how are general ethical rules applied to specific situations? What social processes are important in how individuals reach or fail to reach agreement on what constitutes ethical behaviour? My research is concerned with environmental ethics and the ethical aspects of social issues.

A working assumption of much research on values, conducted in the Rokeach (1973) tradition, is that an individual's value system is fairly stable. Since values are the standards that the self uses to judge and justify itself, the stability of value systems is necessary to express the coherence of the self over time and situations. Value systems are seen as guides that help individuals choose appropriate behaviours and social positions and make decisions.

One implication of this view is that individuals have a single, coherent value system that serves the above purposes. Virtually all research on values measures the value system by asking subjects to rate or rank order a set of values according to how important they are as guiding principles in their lives. In previous research, individuals typically are not asked to consider their value system with regard to any specific issue, such as abortion or the environment.

Recently, my research has examined the dynamics of value systems. We suggest, in this alternate view, that the value system we construct is very much dependent on the context in which we are asked to do it. In other words, it is suggested that we have multiple values systems. This leads to the hypothesis that values are ranked or rated differently depending on whether individuals are asked to rank values according to general, guiding principles, or with regard to specific target issues. Our research has confirmed this hypothesis for the issues of abortion and the environment, and shown that the patterns of value importance associated with different value systems are differentially effective in predicting attitudes toward social issues. Additionally, we have found that there are separate value systems for different self-states (e.g., the actual-self and the ought-self). We have also shown that contradictions between the two self-state value systems are expressed as negative affect, which has implications for value change. Our current research is aimed at providing evidence that value accessibility mediates the effects of situational context on the structure of the value systems.