Protecting Older Workers Against Discrimination Act - Amends the Age Discrimination in Employment Act of 1967 to specify that an unlawful employment practice is established when the complaining party demonstrates that age or participation in investigations, proceedings, or litigation under such Act was a motivating factor for any practice, even though other factors also motivated the practice (thereby allowing what are commonly known as "mixed motive" claims).

Permits a complaining party to rely on any type or form of admissible evidence, which need only be sufficient for a reasonable trier of fact to find that an unlawful practice occurred. Declares that a complaining party shall not be required to demonstrate that age or retaliation was the sole cause of a practice (thereby rejecting the Supreme Court decision in Gross v. FBL Financial Services, Inc., which requires a complainant to prove that age was the "but-for" cause for the employer's decision).

Authorizes the court, on a claim in which an individual demonstrates that age was a motivating factor for any employment practice and in which a respondent demonstrates that the same action would have been taken in the absence of the impermissible motivating factor, to grant declaratory relief, injunctive relief, and attorney's fees and costs directly attributable only to the pursuit of a claim. Prohibits the court in such an instance from awarding damages or issuing an order requiring any admission, reinstatement, hiring, promotion, or payment.

Applies the same standard of proof to other employment discrimination and retaliation claims, including claims under the Civil Rights Act of 1964, the Americans With Disabilities Act of 1990, the Rehabilitation Act of 1973, and similar laws concerning federal employees.