Generally, to prevail on an ADEA claim, an employee or applicant must show that:
(1) he or she is 40 years old or older,
(2) he or she was adversely affected by an employment action, and
(3) the employer took such action because of the employee or applicant's age.
To show an adverse effect, the employee or applicant must show an actual employment action. Being sworn at, for example, is not a sufficient employment action. Furthermore, although an employee or applicant need not show that age was the only factor that caused the adverse employment action, he or she must show that it was a contributing cause.
As with Title VII and other discrimination actions, ADEA claims may be divided into two general types: disparate treatment and disparate impact. Disparate treatment claims are those that stem from employment decisions which, on their face, were discriminatory. For example, if an applicant seeks to show that he was not hired by an employer because he was over 40 years old, he is asserting a disparate treatment claim.
Disparate impact claims, on the other hand, involve facially neutral policies that have the effect of discriminating against older workers. If an employer seeks to show that a test given to workers to determine their eligibility for promotion disproportionately excluded more older workers, she is asserting a disparate impact claim. Some courts have recognized disparate impact claims in the context of ADEA actions, but others have not. The United States Supreme Court has yet to determine whether such claims should be allowed.
