Under the Age Discrimination in Employment Act, an employer may not discriminate against any employee because of that employee’s age, when the employee’s age is forty years of age or over.
There are two types of ADEA claims: disparate treatment claims and disparate impact claims. Disparate treatment claims allege that the employer failed to hire, failed to promote, or terminated a person above the age of 40, on the basis of the person’s age. Disparate impact claims, on the other hand, allege that while the employer’s employment practices or selection criteria appears to treat people of different ages equally, it has the effect of discriminating against persons 40 years of age or older. In disparate impact cases under the ADEA, a practice that disparately impacts workers over forty is nevertheless acceptable if it is reasonable.