Lying to Speak the Truth: Selective Manipulation and Improved Information Transmission

We analyze a principal-agent model in which an effort-averse agent can manipulate a publicly observable performance report. The principal cannot observe the agent's cost of effort, her effort choice, and whether she manipulated the report. An optimal contract links compensation to both the eventually realized output and the (possibly manipulated) report, since both are informative about effort provision. We show that the optimal contract may incentivize selective manipulation of an unfavorable report by an agent who exerted a high level of effort. Doing so can convert a "falsely" negative report into a positive one, thereby making the report more informative about the agent's effort choice.