The Uniformed Services Employment and Reemployment Rights Act of 1994 (USERRA), forbids an employer to deny “employment, reemployment, retention in employment, promotion, or any benefit of employment” based on a person’s “membership” in or “obligation to perform service in a uniformed service,” 38 U. S. C. §4311(a), and provides that liability is established “if the person’s membership . . . is a motivating factor in the employer’s action,” §4311(c).
Although specifically limited to USERA, the court expressly notes the similar "motivating factor" statutory language in Title VII. Justice Scalia's opinion then discusses intentional torts, proximate cause and agency before concluding:
We therefore hold that if a supervisor performs an act motivated by antimilitary animus that is intended by the supervisor to cause an adverse employment action, and if that act is a proximate cause of the ultimate employment action, then the employer is liable under USERRA.It would seem the cat's paw theory likely will be found appropriate in employment discrimination contexts where "motivating factor" is sufficient to establish liability. But it would not necessarily be appropriate in situations like Gross v. FBL Financial Services, Inc. which required "but for" causation.
Justice Scalia's discussion of tort law, proximate cause and agency principles drew a dissent from Justices Alito and Thomas as being unnecessary. But Justice Scalia's discussion provides ample suggestions for future litigants to discuss liability in terms of intentional tort and agency concepts which provide fertile ground for creative litigants.