"A decision maker weighing an adverse action against an employee should be wary of relying too heavily on the mere insights of a subordinate supervisor. In the end, the subordinate may be biased. While the decision maker may eventually decide that adverse action is warranted, he must be able to show that the decision was made at the conclusion of a thorough, unbiased investigation and wasn't merely the product of a subordinate's influence. Otherwise, the employer may be on the hook for liability." [Marshall v. Rawlings Co. LLC, No. 16-5614 (6th Cir., Apr. 20, 2017)]