29 CFR Part 1630, Regulations to Implement the Equal Employment Provisions of the ADA (Title I Regulations with amendments issued through May 2016)

(3) Medical examinations conducted in accordance with this section do not have to be job-related and consistent with business necessity. However, if certain criteria are used to screen out an employee or employees with disabilities as a result of such an examination or inquiry, the exclusionary criteria must be job-related and consistent with business necessity, and performance of the essential job functions cannot be accomplished with reasonable accommodation as required in this part. (See §1630.15(b) Defenses to charges of discriminatory application of selection criteria.)