Documents show Genesee County Sheriff Robert Pickell received $129,000 in payments to a second county retirement savings account since 1999.
Officials say that money never should have been paid.
The records were released to The Flint Journal after a Freedom of Information Act request.
According to a Journal report published Thursday, officials haven't said how or why the payments were made, but have said the county retirement and human resources offices and not the sheriff are to blame.
County board Chairman Jamie Curtis says the county is investigating the arrangement as it negotiates an agreement to resolve problems with the retirement and health benefits given to Pickell.
He retired from the county prosecutor's office and qualified to draw from his pension before he was appointed sheriff in 1999.
Information from: The Flint Journal, http://www.mlive.com/flint
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