The Supreme Court, in Griggs v. Duke Power Co., 401 U.S. 424, 91 S.Ct. 849, 28 L.Ed.2d 158 (1971), articulated the disparate impact theory and constructed a model of proof that the plaintiff and defendant must use in presenting their cases. In Griggs, the employer required a high school diploma and a passing score on two professionally developed tests. Although the lower courts found no liability because the plaintiff failed to prove that the employer had a discriminatory motive for the requirements, the Supreme Court reversed the decision. The Court stated that Title VII "proscribes not only overt discrimination but also practices that are fair in form, but discriminatory in operation." In a famous quote, the Court said that the "absence of discriminatory intent does not redeem employment procedures or testing mechanisms that operate as 'built in headwinds' for minority groups and are unrelated to measuring job capacity."
In the three-step model defined by the Griggs Court, the plaintiff must first prove that a specific employment practice adversely affects employment opportunities of Title VII protected classes. If the plaintiff can establish a disparate impact, the employer must demonstrate that the challenged practice is justified by "business necessity" or that the practice is "manifestly related" to job duties. The courts, between 1971 and 1989, used these two phrases interchangeably. If the employer does not meet the burdens of production and persuasion in proving business necessity, the plaintiff prevails. If the employer does meet these burdens, the third step requires the plaintiff to demonstrate that alternative practices exist that would meet the business needs of the employer yet would not have a discriminatory effect.
The plaintiff has the burden of persuading the fact finder that the employment practice used by the employer adversely affects the employment opportunities of a Title VII protected class. If the plaintiff fails to meet this burden, the court will dismiss the action under Rule 41(b) of the Federal Rules of Civil Procedure.
Demonstrating that the employer's workforce does not reflect the racial, ethnic, or gender percentage of the population of the area does not prove disparate impact. Such an imbalance may be the product of legitimate factors, such as geography, cultural differences, or the lack of unchallenged qualifications for the job. Therefore, it is incumbent upon the plaintiff to show that the imbalance is because of the challenged practice. The most compelling evidence of disparate impact is proof that an employment practice selects members of a protected class in a proportion smaller than their percentage in the pool of actual applicants, or, in promotion and benefit cases, in a proportion smaller than in the actual pool of eligible employees.
If the plaintiff proves that the employer's practice had a disproportionate impact on a protected class, the burden shifts to the defendant to justify its use of the challenged practice. Griggs labeled this burden as business necessity, but suggested that exclusionary practices would be justified if they were manifestly related to job duties. Disparate Impact legal definition of Disparate Impact. Disparate Impact synonyms by the Free Online Law Dictionary.