Auditor General Jack Wagner said Tuesday that governmental entities should not be using swaps, given the risk they carry and fixed-rate borrowing being cheap.
Turnpike officials say Wagner used incorrect methods to calculate the financial impact of the swaps.
Wagner also criticized the commissioners for expenses that included hotel stays that sometimes exceeded $300 a night and an overall "lack of transparency" in accounting for the costs.
Wagner says the turnpike also should install fire detection systems in all its tunnels and have more rigorous procedures to follow up on tunnel inspections.
Wagner's term expires next week.