ly, must the plaintiff identify the specific practice which caused the disparate impact (showing the causal connection between the practice and the impact) or may the plaintiff simply show that an imbalance has occurred? This particular problem was not addressed by the Court in Griggs; indeed, in Griggs the plaintiff identified the particular employment requirements, a high school diploma and a general intelligence test, while the court noted the causal connection between the requirements and the impact on minority applicants. The Supreme Court cases following Griggs did not deal with this question either since the plaintiffs in all of the cases identified the employment criteria and presented evidence of causal connection. In Watson v. Fort Worth Bank and Trust, the last case before Wards Cove, the Court stated that plaintiffs must identify the specific employment practice and present evidence that this practice caused the impact upon minorities; this statement, however, was dicta, as was all of the opinion concerning disparate impact (the case concerned disparate treatment).
Most Circuit Court of Appeal decisions have stated that the plaintiff need not identify any single employment practice which is alleged to have disparately impacted upon minorities; they have also been ambiguous as to whether or not the plaintiff must show a causal connection between the employment practices and the imbalance complained of. The D.C. Circuit Court of Appeals stated that since the employer will possess more knowledge than its employees as to how its practices affect its employees the employer should have the burden of "articulating which of its employment practices adversely affect minorities." On the other hand, the 3rd Circuit stated that while a plaintiff need not identify any single component of a multicomponent selection procedure he must make a "prima facie showing that the disparity would not have occurred except for the employer's hiring ...