Through the use of Greyball, Uber was capable of targeting selected individuals, for example local police, with a fake version of the app that displayed fake cars that would never arrive if contacted. This was developed with the intention of evading the law where the company's practices had been deemed illegal.

Uber's "Greyball" tool was a highly controversial software program used to identify and evade law enforcement and regulators in cities where Uber was operating illegally or without proper permits. The tool identified officials (like police or taxi inspectors) using geofencing, credit card data, and social media mining. When an official opened the app, they would see a "greyballed" version of the map—either with fake cars that would never arrive or a screen saying no cars were available. While Uber initially claimed it was for protecting drivers from "hostile" riders, a 2017 New York Times investigation revealed its true purpose. Following the expose, the U.S. Department of Justice launched a criminal investigation into the practice. While no high-level criminal convictions were directly tied to its use in the US, the practice was widely deemed an illegal obstruction of government functions and a violation of local transport laws, leading to a permanent ban of the tool by Uber in 2017.