You may be asking: how is a cat’s paw relevant to employment discrimination? In Staub v. Proctor Hospital , the US Supreme Court answered that question by holding employers liable for employment discrimination under a theory derived from a 17th-century French fable made famous by poet Jean de La Fontaine. In the fable, a monkey convinces a cat to steal chestnuts roasting on a fire. After the cat has done so, burning its paws in the process, the monkey makes off with the chestnuts and leaves the cat with nothing. In the employment discrimination context, the "cat’s paw" is a "tool" or "one used by another to accomplish his purposes."

The issue in Staub was under what circumstances an employer could be held liable for employment discrimination based on the discriminatory animus of an employee who influenced, but did not make, the ultimate employment decision.

The plaintiff in Staub was an Army reservist who sued his former employer under the Uniformed Services Employment and Reemployment Rights Act (USERRA) after he was discharged for what he alleged to be false accusations made by his supervisors. The plaintiff argued a cat’s paw theory of liability at trial, i.e., that even though the human resources executive who fired him did not have a discriminatory motive, his direct supervisors, who had openly expressed an antimilitary sentiment, influenced the decision to such an extent that their unlawful motive should be imputed to the executive’s actions, and thus the employer. The Supreme Court ultimately agreed, and held that if a supervisor performs an act motivated by discriminatory 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 for discrimination.

In reaching its decision, the Court explained that the mere "exercise of judgment by the decisionmaker does not [automatically] prevent the earlier agent’s action (and hence the earlier agent’s discriminatory animus) from being the proximate cause of the harm." Instead, "[p]roximate cause requires only ‘some direct relation between the injury asserted and the injurious conduct alleged,’ and excludes only those ‘link[s] that are too remote, purely contingent, or indirect.’" Thus, a supervisor’s biased report may remain a causal factor in the employment decision if the ultimate decision maker takes it into account during an independent investigation without first determining that the adverse action was, apart from the supervisor’s recommendation, entirely justified. However, "if the employer’s investigation results in an adverse action for reasons unrelated to the supervisor’s original biased action . . . then the employer will not be liable."

Although the plaintiff in Staub sued under the USERRA, the Court pointed out that the statute was "very similar to Title VII." Thus, the cat’s paw theory of liability should be equally applicable to discrimination claims under Title VII. The Court also clarified that it was "express[ing] no view as to whether the employer would be liable if a co-worker, rather than a supervisor, committed a discriminatory act that influenced the ultimate employment decision."

The practical implications of Staub are somewhat compelling, and should serve as a wake-up call for employers when determining whether to rely upon a supervisor’s recommendation to take adverse action against an employee. In situations where the employee has alleged that a supervisor has a discriminatory motive in seeking the adverse action, the employer should be certain to conduct a thorough, independent investigation into the employee’s allegations to determine whether discrimination underlies the supervisor’s recommendation. Where the supervisor has displayed a discriminatory animus towards the employee in issuing discipline, the employer should ignore the supervisor’s recommendation and the discrimination-based discipline when determining whether adverse action is still warranted.