The review also found that the agency equips each commissioner with a car but puts no limits on its use.
"Commissioners have complete autonomy regarding their expenses and turnpike-owned vehicle usage," the auditors wrote. "We believe government officials should be held to a higher standard, and that excessive and undocumented expenses should not be permitted nor reimbursed."
The report criticized other practices at the agency, such as interest-rate swaps that Wagner said cost taxpayers more than $100 million over nearly five years and a policy of letting employees ride the turnpike toll-free even for personal travel, at a cost of millions in lost revenue.
In a written response, the turnpike's acting chief executive officer, Craig R. Shuey, speaking for the commissioners, said the agency did not agree with all the findings and recommendations. But Shuey promised that his agency would keep working to improve its internal policies and controls.
While Shuey's statement did not address commissioners' expenses, his agency's point-by-point rebuttal of the findings said the audit covered a period - January 2007 to August 2011 - when commissioners had to travel more than usual.
That was when the state was considering leasing the turnpike and tolling portions of I-80, requiring commissioners to go to Harrisburg more frequently for hearings and other meetings, the rebuttal said.
Wagner's report found that while commissioners sometimes attended out-of-town meetings or conferences, most of their travel was to Harrisburg for twice-monthly commissioners' meetings. The turnpike's rebuttal said it was trying to save money by meeting once a month via teleconference.
The audit did not name specific commissioners, Wagner said, because it is his office's policy not to do so and also because some commissioners have since left the agency.
Unlike other turnpike employees, commissioners are not bound by per-diem limits or lodging allowances, though they are required to provide receipts for expenses over a certain amount.
The report said commissioners rarely submitted much besides credit-card statements, along with thinly worded descriptions of expenses, when seeking reimbursement.
The report said one commissioner submitted a bill for a $174 meal near the Harrisburg headquarters in 2009 without a restaurant receipt. Another meal cost $494 at a restaurant in downtown Harrisburg in 2010. Of the latter, auditors wrote: "We would hope it represented a meal for a large group of people conducting turnpike business and involving no alcohol," but said they could not be certain because of the lack of documentation.
Auditors cited "excessive charges" between 2008 and 2011 at the Hilton hotel in Harrisburg. They noted that the government rate for a standard room there was $179, but that commissioners submitted credit-card statements showing charges exceeding $300 per night.
"Commissioners either opted for more luxurious room accommodations, or other hotel charges were included," auditors wrote. "However, here again, because no itemized receipts were included . . . it was difficult to verify the nature of these expenses."
The audit recommended that the commission cap commissioners' expenses, require itemized receipts and other documentation, and stop providing commissioners with cars, instead reimbursing for mileage incurred for work only.
In all, the report found commissioners racked up $539,000 in expenses between 2007 and 2011, including $45,992 for lodging, $15,356 for meals, and $406,497 for cars.
Contact Angela Couloumbis at 717-787-5934 or firstname.lastname@example.org, or follow on Twitter @AngelasInk.