Interpreted the federal statute prohibiting employment discrimination to also prohibit "disparate impact," meaning employer policies that generate unequal employment outcomes regardless of whether the employer provably intended for them to do so, if those policies are not necessary for the employer's business purposes. Decided March 8, 1971 (argued December 14, 1970). Opinion of the Court: Warren E. Burger → go there Topic: Discrimination based on race and ethnicity. Griggs v. Duke Power Co., 401 U.S. 424 (1971), was a court case argued before the Supreme Court of the United States on December 14, 1970. It concerned employment discrimination and the disparate impact theory, and was decided on March 8, 1971. It is generally considered the first case of its type. Wiki link