Disparate impact cases revolve around the reasoning for a rule. A rule which is "reasonably designed and administered to achieve a legitimate business purpose in light of the circumstances," including its potential harm to a protected class, is legitimate. This is why an employer like a fire department, or a moving company, can have fitness qualifications, even though these have a disparate impact on the elderly, while age is a protected class.
The EEOC identifies the following criteria to help evaluate the soundness of a rule:
- The extent to which the factor is related to the employer's stated business purpose;
- The extent to which the employer defined the factor accurately and applied the factor fairly and accurately, including the extent to which managers and supervisors were given guidance or training about how to apply the factor and avoid discrimination;
- The extent to which the employer limited supervisors' discretion to assess employees subjectively, particularly where the criteria that the supervisors were asked to evaluate are known to be subject to negative stereotypes;
- The extent to which the employer assessed the adverse impact of its employment practice on the protected class; and
- The degree of the harm to individuals within the protected class, in terms of both the extent of injury and the numbers of persons adversely affected, and the extent to which the employer took steps to reduce the harm, in light of the burden of undertaking such steps.
I'd comment on applying this to Colorado but it is meaningless because there's not actually a disparate impact.