[W]e must take this opportunity to make clear that retaliatory motive need not be the sole, or even primary, cause of the challenged employment action; rather, it need only be a (not 'the') but-for cause of the decision.
The Court further advised:
The fact that other, non-retaliatory reasons may have contributed to an adverse employment action does not necessarily preclude recovery, so long as there is evidence sufficient to permit the factfinder to conclude that unlawful retaliatory motive was so integral to the adverse action that more likely than not the action would not have been taken had the employee not engaged in protected activity.
The upshot of all this: retaliation or discrimination need not be the only factor, reason or basis for an adverse employment action to sustain a claim under the KCRA but it must be a significant factor.
Powell is an important decision for Kentucky discrimination and retaliation law and been the subject of previous posts: Retaliation Claims Under the Kentucky Civil Rights Act and But For Causation and Retaliation Claims Under the Kentucky Civil Rights Act.