CHICAGO (WCCO) — Chicago Mayor Rahm Emanuel is trying to influence Minnesota’s investigation of Accretive Health.

President Barack Obama’s former Chief of Staff sent a letter to Attorney General Lori Swanson, defending the Chicago-based company, saying it “does important things for hospitals and good things for our City, particularly for our neediest citizens.”

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It was two weeks ago that Swanson announced an investigation by her office that found Accretive employees using aggressive tactics to collect payments from patients.

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Emanuel is urging his fellow Democrat to resume talks with Accretive privately and asked to “cease efforts to publicly prosecute” the matter.

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Swanson says the Accretive CEO has declined her invitation to meet. She says the investigation will continue as “a law enforcement matter.”