As the government shutdown moves into its second week, senators are turning their attention to a law that blocks furloughed federal employees from even checking their government email accounts.

Once the shutdown ordeal ends, Homeland Security and Governmental Affairs Chairman Thomas R. Carper, D-Del., is one of several senators interested in reviewing the statute that governs the shutdown.

“The Anti-Deficiency Act dates back to the late 19th century and has been amended a number of times since then to prevent the government from incurring expenses in the absence of adequate spending authority, which under the Constitution can only be granted by Congress,” Carper said in a statement to CQ Roll Call.

“However, this latest shutdown has raised questions about some of the Anti-Deficiency Act’s provisions and how it is being implemented,” added Carper, whose committee would have a jurisdiction. “Once this shutdown has been resolved and the federal government is again open for business, the Committee will be in a better position to review current law and practice to ensure that it best meets our nation’s needs.”

Republicans have criticized the Obama administration for taking actions that appear unreasonable — blocking access to open-air parks and playgrounds, for instance — but the last significant revisions to the underlying law came in 1982.

Sen. Jeff Sessions, R-Ala., had experience implementing law during a lapse in appropriations back then.

“When I was United States attorney in the early ’80s — under Reagan — there was a shutdown for several days,” Sessions said. “So we had the legal papers that came, and there’s a statute that prohibits a government agency from conducting operations that haven’t been authorized or appropriated by the United States Congress.”

Sessions said the law is “worth looking at.” He said he supports broader use of the emergency exemptions for bodies such as the Federal Emergency Management Agency and the intelligence services.

A member of the Judiciary Committee, Sessions said he was troubled by the determination that more than 70-percent of the intelligence workforce didn’t meet the legal definition of essential workers. At a Judiciary hearing last week, Director of National Intelligence James R. Clapper Jr. called the shutdown and intelligence agency furloughs a “dreamland” for foreign spy services looking to recruit Americans.

While the weekend’s announcement by Defense Secretary Chuck Hagel that most Defense Department civilians would be returning from furloughs largely helped the problem, Senate Intelligence Chairwoman Dianne Feinstein is still concerned about the larger issue that led to the original determination.

“I think there are going to be changes made,” the California Democrat said. “I think the 72-percent figure for intelligence is not sustainable without major loss and jeopardy.”

Sen. Susan Collins, R-Maine, said likewise over the weekend, placing much of the criticism on the Obama administration’s legal determination.

“I’m very disappointed in the furloughing of the intelligence community workers because I think it’s entirely unneccesary, and when the last shutdown — extended shutdown — occurred when President Clinton was in office he kept the NSA fully functioning,” Collins said. “So, I think frankly this is an example of the president making an unwise decision and trying to make this as difficult as possible, but he’s doing so at great risk.”

There are a few circumstances in which programs that operate with appropriated funds get exempted from the shutdown under the existing law, most notable an emergency exception.

Office of Management and Budget Director Sylvia Mathews Burwell noted in a memorandum last month the limits of that exception.

“As the Antideficiency Act states, the emergency exception does not authorize the continuation of ongoing, regular functions of government, the suspension of which would not imminently threaten the safety of human life or the protection of property,” Burwell wrote in the Sept. 17 memo.

It’s that imminent threat language that Clapper cited in testimony before the Judiciary Committee.

Another reason cited by Burwell to exempt personnel from furloughs could conceivably give cover to a broad array of Senate staffers. An exemption is available for an activity if “the function is necessary to the discharge of the President’s constitutional duties and powers.”

It would seem difficult to fully exercise the appointment power without the advice and consent of the Senate. However, the extent to which some lawmakers on both sides of the Capitol have exercised discretion has been a matter of dispute.

Some members of Congress continue to operate their offices with a full staff, while others maintain a skeleton crew. Asked over the weekend if he thought the Antideficiency Act needs an overhaul, Florida Democratic Sen. Bill Nelson conceded he was not particularly familiar with the law but offered an anecdote.

“I called the Senate lawyer, and I said, ‘Look, I’m not shut down, why can’t I keep all of my people?’ and they mentioned this Antideficiency Act and so I don’t, I don’t know,” Nelson said. “I just don’t know anything about it.”

While the Antidefiency Act is always in effect and there are prosecutions for more routine cases where federal employees spend or commit to spend money that hasn’t been appropriated, it’s clearly a much bigger deal when there are no regular spending measures in effect.

That’s probably why the law, which goes back to 1870, so seldom comes up for debate in the halls of Congress.

“The last discussions on the Antideficiency Act that I remember go back to, I believe the Nixon administration.” Collins said. “There is not a lot of discussion.”