Government didn't shut down over the budget til Carter asked his AG to review anti-deficiency act.
Fascinating history of the budget and government shutdowns:
http://bigstory.ap.org/article/closed-business-government-shutdown-history-0
A stickler for the rules, Carter asked his attorney general to look into the Anti-Deficiency Act. In April 1980, Attorney General Benjamin Civiletti issued a startling opinion. "The legal authority for continued operations either exists or it does not," he wrote.
When it does not, government must send employees home. They can't work for free or with the expectation that they will be paid someday.
What's more, Civiletti declared, any agency chief who broke that law would be prosecuted.
Five days later, funding for the Federal Trade Commission expired amid a congressional disagreement over limiting the agency's powers. The FTC halted operations, canceled court dates and meetings, and sent 1,600 workers packing, apparently the first agency ever closed by a budget dispute.
Embarrassed lawmakers made a quick fix. The FTC reopened the next day. The estimated cost of the brouhaha: $700,000.
Near the end of his term, Civiletti further clarified the law's meaning. In a government-wide shutdown, the military, air traffic control, prisons and other work that protects human safety or property would continue. So would things such as Social Security benefits, which Congress has financed indefinitely.
http://bigstory.ap.org/article/closed-business-government-shutdown-history-0