Members of the FBI served the city of New Britain with a grand jury subpoena Thursday as part of the Erin Stewart investigation.
Agents are requesting all records surrounding Stewart's taxpayer-funded credit card, her membership to The Hartford Club, and a charity she oversaw.
An outside law firm had previously found more than $200,000 of personal expenses charged to Stewart's city-issued credit card.
After a criminal investigation was opened, Stewart dropped her Republican bid for governor.
New Britain is demanding Stewart pay the money back by July.
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