(CN) - The Justice Department has opened a criminal investigation into Uber Technologies' use of a software tool, known as "Greyball" that helps its drivers evade local authorities trying to clamp down on the popular ride service.
The existence of the criminal probe was first reported by Reuters. Both the Justice Department and Uber have declined to comment on the matter.
The Greyball software was originally developed to help drivers ferret out illegitimate ride requests, but it also included a feature that obscured the true location of Uber cars, such as when a new feature is being tested or when drivers are called to high crime locations.
But officials in some communities, including Portland, Oregon, say Uber drivers have been using the technology to venture, undetected, into areas where Uber service has not yet been approved.
The city of Portland, Oregon, says in an April audit report that it was notified of the inquiry by the U.S. Attorney's Office in San Francisco. Portland says it is cooperating.
Reuters reported that the investigation may involve a grand jury.
Uber reportedly told its drivers to stop using Greyball for this purpose after The New York Times revealed its existence in March.
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