A legal doctrine holding that policies without discriminatory intent can still violate civil-rights law if they produce disproportionate outcomes along racial or gender lines. The concept was revolutionary when it emerged in the early 1970s, establishing that discrimination could occur without deliberate intent.
The doctrine received its greatest endorsement in the Supreme Court case Griggs v Duke Power Co., decided unanimously in 1971. A power plant in North Carolina had required job applicants without degrees to take IQ exams on which white candidates passed at nearly ten times the rate of black ones. The justices ruled this was directly traceable to race—particularly the poor education given in segregated schools—and therefore violated the Civil Rights Act of 1964, which "proscribes not only overt discrimination, but also practices that are fair in form, but discriminatory in operation".
The federal government abolished its main civil-service exam because of discrimination lawsuits rooted in the doctrine. The Equal Employment Opportunity Commission promulgated a "four-fifths" rule, under which any selection procedure resulting in a pass rate for any race, sex or ethnic group less than 80% of the highest-performing group would be regarded as having "adverse impact". Because the rules required private monitoring and enforcement, they encouraged the rise of professional HR departments.
Under Barack Obama, schools were pushed to remake discipline policies because black pupils were suspended and expelled at greater rates than white pupils. Providers of public housing were discouraged from asking for criminal records of potential tenants. Under Joe Biden, the Federal Communications Commission defined digital discrimination to include actions "that differentially impact consumers' access to broadband internet access service based on their income level, race, ethnicity, colour".
On April 23rd 2025 Donald Trump signed an executive order entitled "Restoring Equality of Opportunity and Meritocracy", aiming to extirpate disparate-impact reasoning "in all contexts to the maximum degree possible". Trump's order could be rescinded by a successor, but the combined effect of the order and the downsizing of civil-rights divisions in the Departments of Justice and Homeland Security may prove lasting: federal agencies will go years without bringing disparate-impact cases, and reviving the concept may be difficult because disparate-impact lawsuits and the racial balancing they encourage are not popular with voters.
In a 2009 opinion (on a case about exams administered by a fire department), the late Supreme Court Justice Antonin Scalia wrote that the court had "merely postponed the evil day on which the court will have to confront the question: whether, or to what extent, are the disparate-impact provisions of Title VII of the Civil Rights Act of 1964 consistent with the constitution's guarantee of equal protection?" A future Supreme Court case could strike down the whole concept as unconstitutional; given the court's conservative supermajority, such a ruling is not expected to favour progressives.
In 1985 the Canadian Supreme Court ruled in favour of a Seventh-Day Adventist who had been sacked from working at Sears because the company required all employees to work on the Sabbath, calling it a case of "adverse effect discrimination". European law recognises the analogous idea of "indirect discrimination". It was codified into British law through the Equality Act of 2010, though similar ideas existed in the Sex Discrimination Act of 1975 and the Race Relations Act of 1976. In 2017 the British Supreme Court upheld indirect-discrimination claims in a case involving a standardised test taken by immigration officers seeking promotion.
birth, n: The first and direst of all disasters.