While ridehailing has made bold promises to resolve the Last Mile problem and get cars off the streets, in reality, it has done little to reduce our dependence on automobiles. If anything, ridehailing has increased congestion in most big cities since it took off in 2010. And, according to a recent study by the Booth School at the University of Chicago, companies like Uber and Lyft have increased traffic deaths in the United States.

The study, titled “The Cost of Convenience: Ridesharing and Traffic Fatalities,” indicates that cities where Uber and Lyft are in widespread use totalled three percent more miles driven daily on average. The study found that, nationwide, the introduction of ridehailing services resulted in a two to three percent increase in traffic deaths of both vehicle riders and pedestrians – which is as many as 1,100 additional deaths each year.

And rather than decreasing congestion, the study indicates that ridehailing services are in fact making it much worse, while increasing gas consumption and new car registrations.

One of the main reasons that Uber and Lyft increase congestion is because of what is called deadheading – which is basically¬†the time that they spend driving around the streets without passengers. Some estimates put the time that drivers spend deadheading at 40 and 60 percent of their total time. And, according to the study, “…rideshare companies often subsidize drivers to stay on the road even when utilization is low, to ensure that supply is quickly available.”

According to one report, Uber and Lyft drivers get scant training, have little experience as professional drivers, and undergo few if any quality control measures.

Ridehailing giants like Uber claim to make streets safer because of their ability to reduce the number of drivers driving under the influence (DUI). A study of the Chicago area earlier this year confirmed that access to ridehailing services did in fact reduce DUI arrests. According to the Booth School study, however, there is no evidence that Uber and Lyft have in fact reduced traffic deaths due to DUI.

According to a report published earlier this year by Schaller Consulting titled “The New Automobility: Uber, Lyft and the Future of American Cities,” usage of transportation network companies (TNCs) like Uber and Lyft is largely concentrated in big, metropolitan cities. And far from reducing reliance on cars, they’ve actually increased it, the primary reason being that they draw customers that would otherwise have used public transportation.

One of the solutions that has been proposed to reign in ridehailing services is to tax TNCs like Uber and Lyft rather than implementing congestion charges, which invariable affect the drivers.

Earlier this year, Uber CEO Dara Khosrowshahi announced plans to integrate the rideshare giant into public transport, amid much protestation. At an event in New York in February, Khosrowshahi said that he wanted Uber to be a service that people could use alongside public transport through a fully integrated transport service.