Ridesharing apps like SideCar and Lyft match drivers who have an extra spot in the car with passengers who need a lift. It’s like hitchhiking, except that the passenger has the option of tipping via the app. The service is growing in popularity, but local regulators are cracking down as it becomes available in more cities, calling ridesharing unsafe.

Over the weekend, the New York City Taxi and Limousine Commission (TLC) stopped two SideCar drivers in a sting operation. The agency used the app to order two rides, then detained the drivers. One woman was allowed to go home, while the other woman was issued a citation and her car impounded. In response, SideCar has called upon the public to phone the city and tweet about the issue, citing a survey that says 83 percent of New Yorkers are in favor of ridesharing.