82 Texas Law Review 975 (2004)
Within the field of psychometrics, it is widely acknowledged that test-taking speed and reasoning ability are separate abilities with little or no correlation to each other. The LSAT is a univariate test designed to measure reasoning ability; test-taking speed is assumed to be an ancillary variable with a negligible effect on candidate scores. This Article explores the possibility that test-taking speed is variable common to both the LSAT and actual law school exams. This commonality is important because it may serve to increase the predictive validity of the LSAT. The author obtained data from a national and a regional law school and followed the methodology of a typical LSAT validity study, with one important exception: student performance was disaggregated into three distinct testing methods with varying degrees of time pressure: (1) in-class exams, (2) take-home exams, and (3) papers. Consistent with the hypothesis, the data showed that the LSAT was a relatively robust predictor of in-class exams and a relatively weak predictor on take-home exams and papers. In contrast, undergraduate GPA was a relatively stable predictor on all three testing methods.
The major implication of this study is that the current emphasis on time-pressured law school exams increases the relative importance of the LSAT as an admission criterion. Further, because the performance gap between white and minority students tends to be larger on the LSAT than UGPA (the other important numerical admissions criteria), heavy reliance on time-pressured law school exams is likely to have the indirect effect of making it more difficult for minority students to be admitted through the regular admissions process. The findings of this study also suggest that when speed is used as a variable on law school exams, the type of testing method, independent of knowledge and preparation, can change the ordering (i.e., relative grades) of individual test-takers. The current emphasis on time-pressured exams, therefore, may skew measures of merit in ways that have little theoretical relationship to the actual practice of law. Finally, this study found some preliminary evidence that the performance gap between white and minority students may be smaller on less time-pressured testing methods, including blindgraded take-home exams. Definitive evidence on this issue will require a larger sample size.
Henderson, William D., "The LSAT, Law School Exams and Meritocracy: The Surprising and Undertheorized Role of Test-Taking Speed" (2004). Faculty Publications. Paper 344.