Denver’s auditor on Tuesday issued a subpoena for three strip clubs to produce payroll records amid an investigation into whether the businesses misclassified dancers as non-employees to avoid paying them the minimum wage and overtime.

The auditor’s office said a hearing officer ordered operators at PT’s Showclub, Diamond Cabaret and PT’s Centerfold to respond before Sept. 24, after which the businesses face paying fines of up to $1,000 per day.

It’s the first time that the auditor’s office deployed its subpoena authority, which the Denver City Council approved last April.

Denver Labor, which operates under the city’s auditor, is investigating whether the clubs “misclassified” its workers as non-employees in order to not pay them the minimum wage, overtime, paid sick leave, and earned tips.

No conclusions have been reached, the auditor’s office said.

Specifically, the office is looking for specific records related to contracts, contact information, and dancers’ payment. The office said it asked the clubs for those records before finally issuing a subpoena.

“This is the first time we are using this subpoena power and without it we would be unable to conduct our investigation into whether dancers’ rights are being violated,” Denver Auditor Timothy O’Brien said.

If all three clubs don’t respond to the subpoena request, a $1,000-per-day fine could be levied.

RCI Hospitality Holdings, Inc., which operates several Colorado clubs, owns Diamond Cabaret, PT’s Centerfold and PT’s Showclub. City officials shut down the PT’s at1601 W. Evans Ave. for two weeks this January after reaching a settlement with the operator over allegations of prostitution and public indecency.

A follow-up investigation by the Denver City attorney’s office and the Denver Police showed that there have been no new instances of prostitution-related legal breaches at the club since July.

Almost a month ago, the Central City Council voted to keep strip clubs out of its historic downtown, which included a proposal by RCI to operate in the city. RCI paid more than $2 million for the building at 130 Main Street and plans to open a steakhouse with strippers, much like the Diamond Cabaret in Denver.

RCI has filed a lawsuit against Central City.

The Denver Gazette reached out to RCI officials for comment on Denver’s investigation. Calls and emails were not returned Tuesday.