Book Review: Human Diversity: The Biology of Gender, Race & Class

Murray, C. (2020). Human Diversity: The Biology of Gender, Race & Class.Hachette Group Books.

Charles Murray is nothing less than the Cartographer of Humanity, documenting reliable population ability differences.  Until recently, the Equal Employment Opportunity Commission’s enforcement of Title VII of the Civil Rights Acts of 1964 and 1991 used evidence of group differences (“adverse impact” comparing employment decision-making based on race, color, religion, sex, or national origin) as prima facie evidence of employment discrimination.

Disparate impact has been defined by EEOC since the Supreme Court’s 1971 Griggs decision as a difference in selection rates (less than 4/5ths of the best group’s rate) comparing covered groups and/or underutilization comparing an employer’s workforce to their labor market. Such group selection differences or a group’s underutilization shift the burden to an employer to demonstrate that the employment decision-making is “job related and consistent with business necessity” as defined in EEOC’s 1978 Uniform Guidelines on Employee Selection Procedures. The White House, however, has recently issued an Executive Order (April 23, 2025) challenging the use of the adverse impact prima facie discrimination trigger:

It is the policy of the United States to eliminate the use of disparate-impact liability in all contexts to the maximum degree possible to avoid violating the Constitution, Federal civil rights laws, and basic American ideals.

It is likely that a constitutional “adverse impact” challenge will end up at the Supreme Court in the foreseeable future. So, the inductively reasoned “equality of results” advocates will certainly cherry-pick Murray’s exceptional tome as they did with The Bell Curve. Murray’s contribution to behavioral science reliably documents that objective, job-related decisions do not support the advocates’ political redistributive equity agenda of equal results.

The early map makers described unknown territory as “thar be dragons”—today’s social justice equity advocates?  The Supreme Court likely will ultimately have to decide between equal opportunity and equal employment. This tension between equal opportunity (individuals) and equal results (groups) caused the late Justice Scalia to opine about 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 consistent with the Constitution’s guarantee of equal protection?

Science is defined by prediction: Murray’s Human Diversity will unquestionably provide the reliable information about group ability differences that will illuminate this inevitable constitutional challenge to Title VII’s statistical definition of employment discrimination.