Ruth S. Day / Duke University /

Research Basic Cognition Everyday Cognition

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  Courtroom Cognition How judges and jurors
understand laws and use them
to decide court cases.

Basic Problem Research Approach Legal Domains Law & Psych Papers


How do people understand laws? Why are laws often difficult to understand? The Day Cognition Lab studies basic cognitive processes involved in understanding and applying laws, especially comprehension, memory, problem solving, and decision making. Although legal terminology is often blamed for making laws difficult to understand, other problems are involved as well. We focus primarily on the underlying logical structure, linguistic complexity, and alternative representations of laws.


Who: --potential jurors
--law students

What: --the underlying logical structure of laws
--the linguistic structure of laws
--alternative representations of laws
--the role of prior knowledge in understanding laws

Typical Experiment
Participants study a law (e.g., a brief excerpt from the model penal code), read brief descriptions of cases, then make decisions (e.g., whether the defendant is guilty or not guilty). Laws are presented in either their original form or ones we devise to test logic, language, or representation issues. Basic cognitive processes tested are: comprehension, memory, problem solving, decision making.

Jury Simulation
Same basic approach as experiments, but with multiple jurors who discuss the cases before deciding them.

Implications: --strategies for understanding laws
--jury instructions
--writing laws
--how cognitive processes operate in everyday settings


Research to date has been on:
  --criminal law (e.g., understanding the insanity defense)
--food and drug law (e.g., "duty to warn")
--contracts (e.g., how they change during negotiations)

However the general issues, principles, and approaches extend to all areas of the law. Current work involves using the same research paradigms across disparate areas of the law, to study how people understand the logical structure of laws as well as the language in which they are written.

LAW & PSYCHOLOGY: Joint Degree
As Faculty Advisor to the Joint Degree Program in Law and Psychology at Duke, I help law students develop a curriculum to coordinate their interests in both fields. Some also do research in my cognition lab. In addition to discussing the on-going lab experiments described above, we work on projects that develop from their other interests. In each case, we examine relevant cognitive processes and develop empirical research projects to study them. Recent theses include:
  --"Schemas of the Bench" (Annette Gammon)
  --"Cognitive and Social Aspects of Special Verdicts" (Katherine Miller)

For more information about the Joint Degree Program in Law and Psychology, see descriptions provided by the Law School and Psychology Department.

(on courtroom cognition)

Day, R. S. Understanding the insanity defense: Text vs. alternative
  representations. International Association of Forensic Linguists. Duke University, 1997.

Day, R. S. Guilty or not guilty: Courtroom cognition. North Carolina Cognition
  Conference. North Carolina State University, 1998.

Day, R. S. The model penal code: Alternative representations and cognitive
  consequences. 23rd Annual Interdisciplinary Conference. Jackson Hole, WY, 1998.

Day, R. S. Guilty or not guilty: Comprehension of legal codes. 23rd International
  Congress on Law and Mental Health. Paris, 1998.

Day, R. S. Courtroom cognition. Psychology Department, North Carolina State
  University, 1998.

Day, R. S. Writing and understanding laws: Chicken vs. egg? 24th International
  Congress on Law and Mental Health. Toronto, 1999.

Day, R. S. Guilty or not guilty: Courtroom cognition. Psychonomic Society. Los
  Angeles, 1999.