By Marshall Cohen, CNN

(CNN) -- Attorney General nominee William Barr promised Tuesday that he would "provide as much transparency as I can" regarding final reports about the Russia investigation.

But during hours of questions at his confirmation hearing before the Senate Judiciary Committee, Barr afforded himself some escape hatches and refused to give in to Democratic demands for total transparency.

Special counsel Robert Mueller is still investigating Russian interference in the 2016 election campaign and whether anyone affiliated with President Donald Trump coordinated with the Russians.

When Mueller wraps up, perhaps in the coming months, he'll issue a report to the attorney general. If Barr is confirmed by the Republican-led Senate, as is expected, the first major decision he'll likely face is how to handle a potentially explosive report from Mueller.

Barr's sweeping promises

In his opening statement, Barr promised to "scrupulously" follow Justice Department regulations that dictate how special counsels should operate and how he should oversee the investigation. Barr pledged that under his leadership at the department, Mueller "will be allowed to complete his work."

Then came the part everyone was waiting for. When Mueller breaks his silence in the form of a final report at the end of the investigation, what will Barr release to the public?

"I also believe it is very important that the public and Congress be informed of the results of the special counsel's work," Barr continued in his opening remarks to the panel. "For that reason, my goal will be to provide as much transparency as I can consistent with the law. I can assure you that, where judgments are to be made by me, I will make those judgments based solely on the law and will let no personal, political or other improper interests influence my decision."

At first blush, Barr's early commitments seemed to err on the side of transparency. He also broke with Trump on key Mueller-related questions, earning some praise from Democrats.

Leaving some wiggle room

As the hearing went on, senators from both parties prodded Barr for details about the report. He gave himself lots of wiggle room, and his answers shifted the conventional wisdom in Washington that the public would eventually see at least a portion of Mueller's report.

He also raised the idea that there could be two reports. The first would be written by Mueller and submitted to the attorney general, and "will be handled as a confidential document," Barr said, citing Justice Department regulations that usually require secrecy about decisions on whether to prosecute the targets of a federal investigation.

"And then the attorney general, as I understand the rules, would report to Congress about the conclusion of the investigation," Barr later said, describing his own planned report. "And I believe there may be discretion there about what the attorney general can put in that report."

This led to all kinds of follow-up questions and clarifications from Barr.

"How these (two reports) are going to fit together, and what can be gotten out there, I have to wait. I would have to wait," Barr said, adding that he wants to consult directly with Mueller and Deputy Attorney General Rod Rosenstein, who has been overseeing the investigation.

Pressed by Sen. Dianne Feinstein of California, the ranking Democrat on the Judiciary Committee, Barr said, "My objective and goal is to get as much as I can of the information to Congress and the public."

At the same time, he laid the groundwork to potentially bury key parts of Mueller's work, giving a possible defense for a report that withholds incriminating information about Trump.

Internal Justice Department guidelines say a sitting president cannot be indicted. Barr said that "if you're not going to indict someone, then you don't stand up there and unload negative information about the person. That's not the way the Department of Justice does business."

Parsing the regulations

The department's regulations about Mueller's final report are short and sweet: "At the conclusion of the Special Counsel's work, he or she shall provide the Attorney General with a confidential report explaining the prosecution or declination decisions reached by the Special Counsel."

Nothing in the regulations appears to authorize Barr to release the report from Mueller to Congress or the American public.

Further, the regulations don't require Barr to issue a final, comprehensive report of his own. There isn't any laid-out mechanism for a "final report" from the attorney general at the end of a special counsel probe. That means Barr could have wide discretion on how he summarizes Mueller's findings and what he chooses to keep secret, as long as he follows regular Justice Department rules for public reports.

There are also reporting requirements for the attorney general, who must notify and explain to Congress whenever a special counsel is appointed or fired and upon the conclusion of the investigation. But this section is less than clear on how it could apply to the release of the entire Mueller report.

Some Democrats pounced after the hearing and said Barr wasn't playing fair.

"We now have a situation where an incoming attorney general takes the position, 'You can't indict the sitting president, you can only impeach a sitting president, and I'm not committing to share with Congress or the American people information you would need to know to make a judgment about whether the President's conduct rise to that level,'" Rep. Adam Schiff, the California Democrat who now runs the House Intelligence Committee, said Tuesday on MSNBC.

CNN previously reported that Mueller's report is expected to include extremely detailed analysis and to answer a number of looming questions in the investigation. Likely topics include whether anyone on the Trump campaign illegally coordinated with the Russians who interfered in the 2016 election, whether Trump knew in advance of the June 2016 Trump Tower meeting with Russians and whether any foreign money illegally flowed into his campaign.