This article examines the idea that cognitive load interventions can expose lies—because lying is more demanding than truth-telling. I discuss the limitations of that hypothesis by reviewing seven of its justifications. For example, liars must suppress the truth while lying, and this handicap makes lying challenging such that one can exploit the challenge to expose lies. The theoretical fitness of each justification is variable and unknown. Those ambiguities prevent analysts from ascertaining the verisimilitude of the hypothesis. I propose research questions whose answers could assist in specifying the justifications and making cognitive load lie detection amenable to severe testing.