(CNN) A CNN analysis has found that embattled Environmental Protection Agency Administrator Scott Pruitt paid himself nearly $65,000 in reimbursements from his two campaigns for Oklahoma attorney general, a move at least one election watchdog has sharply criticized as being recorded so vaguely that there was no way to tell if such payments were lawful.

The reimbursement method, which Pruitt used in his 2010 and 2014 campaigns, effectively scuttled two key pillars of campaign finance: transparency about how campaign funds are spent and ensuring campaign funds are not used for personal purchases, according to a former top elections attorney and a CNN review of the documents.

Some of the reporting may also violate Oklahoma campaign finance rules, according to research done by the Campaign Legal Center, a nonprofit and nonpartisan group.

At EPA, Pruitt is under scrutiny for questionable spending and ethical decisions that have landed him in hot water with investigators and on Capitol Hill. Ethics watchdogs, federal auditors and congressional committees are conducting nearly a dozen inquiries into Pruitt's actions at the agency

During his attorney general bids, records show Pruitt made purchases and then received reimbursement from his campaign -- sometimes thousands of dollars apiece -- rather than having the campaign pay directly for expenses like renting a vehicle or purchasing a meal. When purchases are made directly, the campaign filings would show more details about who received the payments.

Instead, dozens of entries on Pruitt's 2010 and 2014 campaign finance filings show payments to him but don't have the same level of detail, making it difficult to tell if the purchases were legitimate.

The reimbursements are vaguely stated as being for meals, travel, office supplies, phone service, internet access and office decorations, and in some cases do not list the the vendors.

A spokesman for Pruitt, Jahan Wilcox, described the payments to CNN as "standard reimbursements."

"This is useless reporting," said Larry Noble, the former general counsel at the Federal Election Commission. He is now at the Campaign Legal Center and is a CNN contributor. "There's no way of telling if this is a personal expense. ... You couldn't do this on the federal (level) -- it's illegal."

Noble said Oklahoma rules require campaigns to "show the ultimate vendor and an adequate description so you know what the item was for." Because some of the payments to Pruitt do not do that, "It was not at all clear that these were all lawful," Noble said.

Noble noted that the campaigns, however, still made direct payments of more than $1.6 million.

"So he's not running the campaign through his credit card," Noble said.

All of the payments were made when Pruitt was a candidate for attorney general or after he had been first elected to the office in 2010. The records do not show any payments since Pruitt became administrator of the EPA last year.

As EPA chief, Pruitt has faced allegations he took advantage of increased security and made travel arrangements for his own benefit -- demanding to fly Delta in order to get frequent-flyer points and staying at posh hotels more expensive than government limits for reimbursement (which also placed an undue burden on his staff who have to pay out of pocket). He's also been accused of excessive spending on his office, like an ornate restored desk and a soundproof booth. In some cases, he blamed the expenditures on his staff.

The reimbursements to Pruitt when he was AG totaled $29,204.87 from the 2010 campaign account and $35,665.73 from his 2014 re-election account, according to the filings.

The filings show Pruitt was frequently reimbursed for dining expenses at The Beacon Club, which was described by a local newspaper as "Oklahoma City's oldest private downtown dining" establishment when it closed last year. "The Beacon Club was where deals got done," The Oklahoman newspaper reported.

Some of Pruitt's reimbursements were for "officeholder expenses" -- meaning items needed for his role as attorney general -- after he was elected in 2010 and re-elected in 2014.

More than $5,000 is for items that appear to be office supplies and decorations. Around $3,600 is described as "Artwork/Decorations" from retailers like Pier 1 Imports, an Oklahoma florist and a local picture framing shop. Records also show Pruitt purchased a $1,400 Apple computer.

Because of the limited information and lack of transparency, it's impossible to determine whether the purchases were appropriate and for official purposes, Noble said.

"Do we know how the campaign spent its money? No," Noble said. "How do you enforce a personal use prohibition unless you know how the money is being used? ... This is not any way you want to have a campaign finance log."

The office purchases were made a mere 10 days after the Bank of America skyscraper in downtown Tulsa agreed to lease office space to the attorney general's office, headed by Pruitt. The move expanded the Tulsa AG's offices and placed them in the same building as Pruitt's campaign offices, raising the rent from about $3,000 per month to $12,000 per month.

The office of current Attorney General Mike Hunter told CNN that around the same time, the AG's office was required to expand and hire more staff.

One Republican source said Pruitt would sometimes leave the AG's office to work from the campaign office in the same building.

His move to Tulsa was seen publicly as a convenience, since he lived in Tulsa and not Oklahoma City, where the AG is headquartered.

Wilcox, the Pruitt spokesman, did not address detailed questions from CNN about the expenditures and decision to relocate his government offices to the same building as his campaign office.