If there are ads on the outside of taxis as well as on their insides, why can’t drivers for ride-hailing apps put up ads of their own? A company that provides an app that turns a driver’s tablet into a ride-hailing version of Taxi TV is suing the city of Chicago, which bans advertising in cars for ride-hailing app services.

The company behind the ad app, Vugo, says that the average driver takes in about $100 per month from ads, and a full-time driver can earn up to $300 per month. The tablets show video content and advertisements to passengers, which can be customized to show ads related to the passenger’s destination.

As a car shows news and entertainment content and ads, 60% of the revenue goes to the driver. Drivers have to provide their own tablets, but are reportedly glad to have the extra income, especially when fare cuts happen.

One of Vugo’s co-founders is a former Uber driver in Chicago who started his company in Minneapolis because of Chicago’s restriction against ads in ride-hailing vehicles. Vugo currently has about 8,000 drivers signed up in its home city of Minneapolis, as well as in San Francisco and Los Angeles.

“There is no difference inherent in those services that justify banning advertising in one while allowing it in the other,” the company’s attorney said at a press conference, referring to ride-hailing app cars and licensed taxis respectively.

The company’s argument is that banning ads in cars that accept fares from ride-hailing apps limits its right to free speech, and presumably also the drivers’ right to free speech.

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