When he was an Oklahoma state senator 15 years ago, Environmental Protection Agency Director Scott Pruitt bought a home with a registered lobbyist.

The New York Times reported that Pruitt did not publicly disclose his financial relationship with the lobbyist, Justin Whitefield, who lobbied for legislative changes to worker compensation rules that benefited businesses. Pruitt then advocated for these same changes.

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The two would occupy the home whenever they were in Oklahoma City on business.

This conflict of interest adds to the pile of ethics cases against Pruitt that have come up in the last several weeks. Pruitt cut a deal with a Washington D.C. condominium owner to pay extremely cheap rent. The owner’s husband is an energy lobbyist whose clients won EPA approval to build a pipeline.

The EPA also failed to disclose an expenditure of over $43,000 on a soundproof phone booth for the EPA director. President Donald Trump was encouraged to fire Pruitt, but instead stood by him.