How long do they have to settle this?

The current funding resolution expires at midnight on April 8. So a shutdown would start Saturday, April 9. Since very few federal employees work on weekends, Congress could stay in session trying to finalize the spending plan to avoid a large-scale disturbance Monday morning.

The White House and congressional leaders are working on a deal that would slash about $33 billion from the federal budget, including $10 billion already cut by two other short-term measures, amounting to the largest reductions in U.S. history.

Several tea party-backed Republicans continue to favor a House-passed measure that would cut $61 billion in spending. House Speaker John A. Boehner (R-Ohio) may turn to moderate Democrats to help pass the compromise in the House, but such a move could compel conservative Republicans to vote against it.

President Obama said Friday it “would be the height of irresponsibility” to force a government shutdown, and urged all sides to quickly strike a deal.

Why does Congress wait so long to pass the budget?

Under a budget law passed in 1974, the House and Senate are supposed to approve the 12 appropriation bills funding the federal government by Sept. 30, the last day of the fiscal year. It almost never happens.

In the past 16 years — 10 of which were controlled by Republicans, four by Democrats and two with mixed leadership in the chambers — Congress did not meet its statutory deadline for approving the spending bills.

Usually the House completes most of its work by late July, then watches as the slower-moving Senate tries to slog through the appropriations, resulting in stopgap resolutions that keep the government funded at the previous year’s spending levels until the two chambers strike a long-term deal.

Years when the party in power is politically vulnerable and on the verge of ouster tend to be the most difficult times. In 2002, on the brink of losing the majority, Senate Democrats could not approve anything except military funding. In 2006, with Republicans on the verge of losses, they also only approved military funding. And last year, on the verge of losing the House, Democrats failed to pass a single appropriation bill.

Now, the GOP majority in the House and the Democratic majority in the Senate are trying to clean up last year’s mess.

What’s the thinking on who’s going to get blamed?

Most Democrats believe the presidential bully-pulpit gives them the advantage if there is a shutdown. Former Democratic Party chairman Howard Dean said as much last week during a television interview.

This assumption is based largely on the shutdowns of 1995 and 1996, when GOP majorities on Capitol Hill earned the blame and then-President Bill Clinton benefited politically.

Rep. Paul C. Broun (R-Ga.) on Friday said Obama and Senate Majority Leader Harry M. Reid (D-Nev.) “orchestrated a plan” to shut down the government to make Republicans look bad.

However, a Washington Post-ABC News poll last month showed that the public would be evenly divided regarding responsibility for a shutdown. And some strategists in each party say a shutdown could be bad for both parties, especially among independent voters, who would see it as a mutually dysfunctional system.

Are shutdowns common?

Not in recent years. Six shutdowns occurred between fiscal 1977 and fiscal 1980. An additional nine occurred between fiscal 1981 and fiscal 1996. The most recent shutdown stretched from mid-December 1995 until early January 1996.

How long do shutdowns normally last?

Shutdowns in the 1970s and 1980s ranged from three days to 17 days, according to the Congressional Research Service (CRS). A five-day shutdown occurred in November 1995, and a shutdown stretching from mid-December 1995 to early January 1996 lasted 21 days — the longest in modern history.

If a shutdown occurs, what would stay open and who would have to work?

We won’t know for certain until it happens.

Federal agencies are drafting contingency plans to determine which functions would continue and who would keep working. But the Office of Management and Budget has ordered agencies not to publicly disclose details, frustrating many federal employees and federal worker union leaders who say the silence is causing confusion in the ranks.

If contingency plans are used, the agency would designate some personnel “essential” (or “emergency” and “excepted,” as OMB officially calls them) and others “non-essential” (or “non-excepted”).

According to the government’s official guidance on shutdown planning, agencies should continue any functions providing for national security, critical foreign relations and the safety of life and property.

In other words, global U.S. military operations would continue, air-traffic controllers would watch the skies and Transportation Security Administration officers would still screen air passengers. Veterans Affairs doctors and nurses would report for duty, as would U.S. Border Patrol agents, federal prison guards, any Federal Emergency Management Agency personnel needed for disaster assistance and security guards protecting federal facilities.

With the growth of government contracting and the wider use of technology, however, an untold number of contractors providing information-technology support and other services might also be instructed to stay on the job.

How many federal workers would be impacted?

The first 1995 government shutdown led to furloughs for about 800,000 federal employees, according to CRS. The second 1995-1996 closure impacted only 284,000 federal employees, because several of the regular spending bills had been passed in the meantime.

An untold number of federal contractors were also impacted; the federal government doesn’t track the number of contractors employed by agencies. The federal government spent $535 billion on government contracts in fiscal 2010 — much more than during the 1990s — meaning thousands of more people could be impacted.

Would federal workers and contractors be paid?

Probably. Although federal employees earned retroactive pay for time lost during the ’95-’96 shutdowns, Congress has never considered repaying contractors.

And with fiscally conservative lawmakers determined to control spending levels, federal worker union leaders are cautioning members not to assume they would receive retroactive pay.

Whether contractors would be paid during an impasse would depend on their employer. Some firms would be able to cover the temporary loss in government revenue, but smaller firms might not, according to government contracting experts.

What would it mean for government contracting firms?

The Washington-area business community began mobilizing for a shutdown weeks ago, urging firms to start speaking with agency officials to determine what services and employees might be affected.

Veterans of previous shutdowns are reminding contractors that they could be locked out of their offices or forced to cut short any government-funded travel.

During a shutdown, experts suggest contracting firms should ask employees to complete overdue training programs, take vacations or temporarily reassign them to other projects.

Worst case, some firms may need to furlough employees.

Boehner on Friday said any shutdown could interrupt contracts and force the government to pay more in eventual overtime costs.

How would a shutdown impact me?

Much of this depends on what the government deems an “essential” or “non-essential” service (see above). Using the ’95-’96 shutdowns as a guide, it could impact the general public in several ways.

Back then, the National Institutes of Health couldn’t accept new patients for clinical research and didn’t answer hotline calls regarding diseases, according to CRS. About 2 million visitors nationwide couldn’t visit national parks, military veterans saw some health and financial services delayed and up to 30,000 applications by foreigners for U.S. visas went unprocessed for each day of the shutdown.

But much has changed since the 1990s. Most federal benefits are now directly deposited, many veterans services are on multi-year budgets not impacted by the current stalemate and the Obama administration may interpret essential services differently than their predecessors.

How would a shutdown impact the District?

Lawmakers refused to appropriate District operating funds during the first 1995 shutdown, but agreed to provide funding during the longer impasse.

The District’s financial relationship with the federal government has changed, but Congress still votes to approve city spending. Lawmakers have yet to do so this year.

If necessary, District leaders and Del. Eleanor Holmes Norton (D-D.C.) are vowing to work closely with the White House and Congress to ensure the city’s continuity of operations.

Shutdown or not, what’s waiting around the corner?

More shutdown threats lie ahead.

Either the White House and Congress will reach an agreement that funds the government through the end of the fiscal year in September, or they will agree to another short-term deal and keep talking.

This year’s negotiations are unique, however, because this is the latest in a fiscal year that the budget has remained undecided, going back at least to Jimmy Carter’s presidency.

Congress is also is nearing a vote on the federal debt limit and soon must begin drafting a budget for fiscal 2012, which begins in October.

Staff writers Mike DeBonis, Felicia Sonmez and Eric Yoder and researcher Lucy Shakelford contributed to this report. For more on the possible government shutdown, visit washingtonpost.com/federaleye.

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