A Medicaid investigator alleges in a recently unsealed lawsuit that a firm hired by the state knowingly processed millions of dollars in fraudulent claims for Medicaid reimbursements and then fired her in retaliation for reporting her suspicions.

Karen Clark, an investigator who had worked for OptumHealth Behavioral Solutions, a subsidiary of UnitedHealth Group Inc., filed the federal lawsuit in April 2013 under the federal False Claims Act, alleging supervisors at OptumHealth looked the other way when nine behavioral health providers submitted false Medicaid claims over a 19-month period, and then they fired her for reporting the suspected fraud to law enforcement.

Clark claims OptumHealth profited from the alleged fraud because the state paid the firm 28 percent of each claim submitted for Medicaid reimbursement.

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