82 Preface LEGAL JUDGMENT AS INFORMATION INTEGRATION

Legal judgments and decisions require valuation and integration of stimulus information. Such information processing is a province of psychological science and many psychologists have taken up legal issues to seek social usefulness. Some issues in legal psychology obey the same mathematical laws of information integration established in other areas of human psychology. This is not surprising; the same cognitive processes operate in all these areas. Person cognition and social attitudes, in particular, are basic in legal psychology. So of course is judgment–decision theory. Some writers disagree. They argue that legal information, such as testimony of witnesses and arguments of prosecution and defense attorneys, is too complicated and too subject to contextual effects to be amenable to simple mathematical analysis. Their argument is nullified by the successes of the mathematical laws—Cognitive Unitization of these laws allows exact analysis of complex context effects. Cooperative use of field observation and laboratory experiments is needed to make legal psychology socially useful. Laboratory experiments can establish validity of cognitive processes, as with the averaging law and generally with functional measurement analysis of multiple coacting variables. Social applications, however, require understanding knowledge systems that operate in social reality. The landmark experimental–field studies of Ebbesen and Konečni and well-designed work by Kaplan and by Hommers provide models for future investigators. This direction of inquiry can help develop a more moral and more humane society.