There are grounds for concern about testing's relationship to the law because where a constitutional issue is involved, the burden of proof of need for the test immediately shifts to educators. Throughout the history of testing in this country, the courts have often intervened to assure that students, while they are in school, are free from discrimination, either in word or act, by school officials. Upon a prima facie showing of discriminatory impact, those doing the testing must demonstrate the rationality of the testing procedures and the validity of the tests. In a case presenting the clearest summary of the requirements of proper validation, the court set up four hurdles that the defendant must clear. First, the test must have differential validity, that is, it must have separate validation scores for all minorities. Second, the level of confidence for the test must be at the .05 level. Third, the testing procedure must contain an adequate sample. Fourth, the test must have been administered to all under uniform conditions--the local use of the test must closely conform to the sample, purpose, and conditions used in the test's validation. (Author/IRT)