State auditors say Michigan improperly spent $160 million over three years caring for Medicaid recipients needing in-home services.
The audit released Tuesday faults the state Community Health and Human Services agencies and includes two "material" findings that are more serious. Auditors warn the state could be forced to repay nearly $100 million to the federal government.
The audit says Michigan didn't have service logs, invoices and other documentation required to support payments made to providers from 2010 to 2013.
State officials agree sufficient documentation wasn't always obtained and say they're fixing the problem. But they say estimated improper payments are extrapolations from limited sample sizes and are too high.
The audit also says state caseworkers didn't complete six-month reviews to ensure clients received the most appropriate care.