A Dolton trustee confirmed the subpoena is seeking records about trips made by village officials and expenses they were reimbursed for.
It also includes payments made to Henyard and the village's chief administrator.
Dolton recently hired former Chicago Mayor Lori Lightfoot to lead an investigation into the same thing.
Henyard did not immediately respond to a request for comment.
A law firm that had been representing Dolton dropped the south suburban village as a client earlier this week, saying it hasn't been paid.
Keith Freeman, a senior administrator for both the village of Dolton and Thornton Township, was also recently charged with engaging in a bankruptcy fraud scheme.
SEE ALSO | Senior admin. for Dolton, Thornton Twp. Keith Freeman arraigned on bankruptcy fraud charges
READ MORE | Lori Lightfoot hired to investigate Dolton Mayor Tiffany Henyard
SEE ALSO | FBI investigates Dolton Village Hall amid corruption allegations about Mayor Tiffany Henyard
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