Former President Barack Obama’s ex-campaign manager received a $90,000 fine on Thursday for illegally lobbying Chicago Mayor Rahm Emanuel on behalf of Uber.

The Chicago Board of Ethics found David Plouffe guilty of not following ethics rules when he did not register as a lobbyist after he contacted Emanuel.

Plouffe was engaged by Uber — the up-and-coming alternative to traditional taxi service — because the company wanted to the city to amend existing bylaws that made it difficult for the company to pick up fares at Chicago airports.

The board also went after Uber with a $2,000 fine for hiring Plouffe — because he broke the ethics rules.

Uber has admitted its error and has agreed to pay the fine.

The Chicago Tribune reports that the matter came to light after Emanuel released hundreds of his personal emails connected to public business because of a two open record lawsuits. The suits accused Emanuel of breaking the state open record law.

Plouffe sent the following message to Emanuel on Nov. 20, 2015:

“Assume both of us thought the airport issue was settled and we would never have to discuss again, but unfortunately two significant new hurdles were introduced,” wrote Plouffe, who was then a senior executive at Uber. “Coming to you because of their severity that would prevent us from operating. We were all set to announce Monday we were beginning pickups.”

Plouffe was hired because of Uber’s concerns over pick-up fees and its desire to get airport regulations changed that insisted Uber cars had to display a company placard when picking up customers. The lobbying effort was initiated at a time when cities across North America were grappling with Uber’s business status and regulations affecting it.

Though both Plouffe and Uber fought for a reduced fine of $1,000, the board did not concur; it ruled that only a stiffer penalty would discourage unregistered lobbying.

According to regulations, Plouffe had five business days to register as a lobbyist after he met with Emanuel. He did not register until April 13, 2016, months later.

“Mr. Plouffe and the company argue that this leads to an absurd result by having the board punish those, like him, to the same degree it would punish a person who actually had engaged in lobbying every day during this period,” the panel wrote in its decision. “The board rejects this argument.”

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