A new General Accounting Office report says Presidents Nixon, Ford and Carter are responsible for the fouled-up condition of the $60 billion federal pay machine. The system that is used to establish white collar and military pay rates is believed to overpay some, underpay others and is known to confuse and enrage taxpayers.

Carter has proposed legislation to "reform" the federal pay system on grounds that it is a mess. GAO agrees, but says -- diplomatically -- the mess was made by the last three people to use the White House.

GAO made its analysis of the Carter plan for Rep. Gladys N. Spellman (D-M.). Like many of her civil servant constituents, Spellman feels the Carter plan would do for pay reform what the Spanish Inquistition did for religious understanding. What Spellman thinks is important. She chairs the House subcommittee that can approve -- or kill -- the Carter pay plan.

In a nutshell, GAO said the federal pay system is badly out of whack because presidents keep shaving annual catch-up-with-industry raises. It said six of the total of 10 proposed annual increases have been altered by presidents.Carter set a 5.5 percent limit on 1978 raises although data indicated a raise of about 8.4 percent was due government workers. This year he allowed rank-and-file employes a 7 percent raise although a boost of around 10.4 percent was indicated by industry wage comparisons.

GAO also was critical of the practice of giving across-the-board raises to federal workers, rather than increases scaled by grade and job.

Ironically, the president's plan would give him more authority to set the size of raises and determine the value of federal fringe benefits that would be matched -- for the first time -- to those in industry.

Backers of the Carter pay reform plan will find data and conclusions in the GAO report to support their contention that reform is badly needed. But many members of Congress -- who are alarmed that pay reform might mean smaller raises for federal employe constituents -- can and will use the GAO findings to oppose pay reform.