WHAT'S OPEN?: Here's how the shutdown is affecting key parts of the federal government

Thomson Reuters

Thousands of federal employees began their weekends gripped with doubt, uncertain of when they'll be able to return to work and how long they'll have to go without being paid after a bitter political dispute in Washington triggered a government shutdown.

And now that the shutdown has extended into the work week, federal employees entered Monday unsure of when their next paycheck would come.

Many government operations will continue — US troops will stay at their posts and mail will get delivered. But almost half the 2 million civilian federal workers will be barred from doing their jobs.

The longer the shutdown continues, the more likely its impact will be felt. Sen. John McCain, R-Arizona, said Republicans and Democrats share the blame.

"Political gamesmanship, an unwillingness to compromise, and a lack of resolve on both sides have led us to this point," McCain said in a statement Saturday.

How key parts of the federal government would be affected by a shutdown:

Internal Revenue Service

Thomson Reuters

A shutdown plan posted on the Treasury Department's website shows that nearly 44 percent of the IRS' 80,565 employees will be exempt from being furloughed during a shutdown.

That would mean nearly 45,500 IRS employees will be sent home just as the agency is preparing for the start of the tax filing season and ingesting the sweeping changes made by the new GOP tax law.

The Republican architects of the tax law have promised that millions of working Americans will see heftier paychecks next month, with less money withheld by employers in anticipation of lower income taxes. The IRS recently issued new withholding tables for employers.

But Marcus Owens, who for 10 years headed the IRS division dealing with charities and political organizations, said it's a "virtual certainty" that the larger paychecks will be delayed if there's a lengthy government shutdown.

Health and Human Services

CDC

Half of the more than 80,000 employees will be sent home.

Key programs will continue to function because their funding has ongoing authorization and doesn't depend on annual approval by Congress.

But critical disruptions could occur across the vast jurisdiction of HHS programs — including the seasonal flu program.

Medicare, which insures nearly 59 million seniors and disabled people, will keep going. And so will Medicaid, which covers more than 74 million low-income and disabled people, including most nursing home residents.

States will continue to receive payments for the Children's Health Insurance Program, which covers about 9 million kids. However, long-term funding for the program will run out soon unless Congress acts to renew it.

Deep into a tough flu season, the Centers for Disease Control and Prevention will be unable to support the government's annual seasonal flu program. And CDC's ability to respond to disease outbreaks will be significantly reduced.

Justice Department

Aaron Bernstein/Reuters

Many of the nearly 115,000 Justice Department employees have national security and public safety responsibilities that allow them to keep working during a shutdown.

Special counsel Robert Mueller's team investigating Russian meddling in the presidential election will also continue working. His office is paid for indefinitely.

The more than 95,000 employees who are "exempted" include most of the members of the national security division, U.S. attorneys, and most of the FBI, Drug Enforcement Administration, Bureau of Alcohol, Tobacco, Firearms and Explosives, U.S. Marshals Service and federal prison employees.

Criminal cases will continue, but civil cases will be postponed as long as doing so doesn't compromise public safety. Most law enforcement training will be canceled, per the department's contingency plan.

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