Disparate Impact and Disparate Treatment
According to Dana Shilling in her book "The Complete Guide to Human Resources and the Law", employment action can be challenged on the basis of a claim of disparate impact discrimination. Under Title VII of the Civil Rights Act of 1964, adverse or disparate impact occurs when a seemingly neutral employment practice unfairly impacts a specific group, and involves unintended but nevertheless unequal consequences for people of different gender, race, religion, color or national origin. An example of disparate impact would be administering written tests for promotions. If these tests has an adverse impact on a protected group measured statistically, members of that group could claim disparate impact. On the other hand, disparate treatment is an overt act. It involves using race, sex, religion, national origin or color as a basis for treating employees differently meaning unfairly and/or unequally. An example would involve refusing to promote other than white males into senior management positions. To prevail in a disparate impact case, the plaintiff must prove, usually through statistical comparisons, that the challenged practice or selection device has a substantial adverse impact on a protected group. If the plaintiff can demonstrate disparate impact, the employer must demonstrate that the challenged practice is job-related for the position in question and consistent with business necessity. It must be noted that even if the employer can prove a business necessity, the plaintiff may still win the lawsuit by showing that the employer refused to adopt alternative employment practice which would satisfy the employer's legitimate interests without having a disparate impact on a protected class (Shilling, 1998).
According to an essay published online by HR Guide, The Supreme Court first described the disparate impact theory in 1971, in Griggs v. Duke Power Co., 401 U.S. 424, 431-2 (1971): Titl...