Via a public records request, Motherboard has obtained a cache of emails between Uber management, including CEO Travis Kalanick, and elected officials including Pittsburgh Mayor William Peduto. In part, they show Uber working closely with Peduto on efforts to push back against state regulators.

Though there is no sign of illegality in the emails, they show Peduto following Uber’s lead in arguing against a fine of $11.4 million, levied against the ride-sharing startup by Pennsylvania’s Public Utility Commission for operating illegally there in 2014. Peduto had multiple conversations with Kalanick and Uber lobbyists before writing a letter urging the Commission to reconsider the fine.

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In the letter, which was also signed by Pennsylvania Governor Tom Wolf, Peduto warns that Uber’s planned investments in Pennsylvania “could be lost if we send the message that Pennsylvania is not a welcoming place for 21st century businesses and other job-creators.”

The emails also show a friendly personal relationship between Kalanick and Peduto, with the Mayor providing direct updates regarding the PUC’s decision, and pinging Kalanick with details of his own Uber use.

This sort of back-room cooperation is a bit of a contrast to Uber’s often very public and hard-nosed approach to pushing regulatory change in cities where it operates. Its aggressive tactics have included leveraging public sentiment against officials, and it has rarely lost—one notable exception being Austin, where the company was unable to reverse a rule requiring strict background checks for drivers, despite spending heavily on a referendum campaign. It responded to the loss by ending service in Austin.

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But Pittsburgh is not Austin. In most cities, leaders must balance public demand for Uber against the interests and influence of taxi operators who oppose the service, and against accusations that Uber erodes wages and safety compared to traditional taxis.

Pittsburgh, by contrast, is the home of Uber’s primary self-driving vehicle research facility, which promises to be a long-term source of high-wage, high-skilled jobs. In the future, that could put it closer to the top of an economy increasingly stratified by automation. For a mayor with a shot at that kind of legacy, it makes perfect sense to play along.