Hanke has also worked as an expert witness in financial litigation, specializing in derivatives cases. In the past, he was a principal at Chicago Partners (now Navigant Consulting). In 1994, Hanke, his then-post-doctoral student Christopher Culp, and Nobel Laureate Merton Miller waded into the debate over the collapse of Metallgesellschaft AG. Although not officially involved in the case, Hanke, Culp, and Miller made headlines when they revealed that Metallgesellschaft's oil futures hedge was sound, and that it was Deutsche Bank who was responsible for the collapse of the $1.3 billion position.