Over a 6-month period, the OIG found in California:

For our sample of 150 beneficiaries, California made Medicaid payments on behalf of 112 eligible beneficiaries. However, for the remaining 38 beneficiaries, California made payments on behalf of ineligible beneficiaries (e.g., a woman who did not meet eligibility requirements for the newly eligible group because she was pregnant) and potentially ineligible beneficiaries (e.g., a beneficiary who may not have met the residency requirement). On the basis of our sample results, we estimated that California made Medicaid payments of $738.2 million ($628.8 million Federal share) on behalf of 366,078 ineligible beneficiaries and $416.5 million ($402.4 million Federal share) on behalf of 79,055 potentially ineligible beneficiaries. (These estimates represent Medicaid payments for fee-for service, managed-care, the drug treatment program, and mental health services.) These deficiencies occurred because California’s eligibility determination systems lacked the necessary system functionality and eligibility caseworkers made errors. We also identified a weakness in California’s procedures related to determining eligibility of individuals who may not have intended to apply for Medicaid.

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