The General Accounting Office says Congress ought to outlaw a federal early-out retirement program that lets agencies clean house at the expense of taxpayers and permits some U.S. workers to retire at the ripe old age of 43.

Under President Carter's civil service reform act, U.S. agencies planning RIFs (reductions-in-force) or reorganizations can offer early retirement to persons with 25 years' service; or anyone age 50 with 20 years in government. Idea was to protect the jobs of less senior workers who might be fired or downgraded because of the changes. However, the congressional watchdog agency says the program has been abused by some federal agencies, and caused a surge in unnecessary retirements of workers in their 40s and 50s.

GAO said many of the early-outs were out justified by RIFs or reorganizations, and that some who quit early were rehired shortly in the same jobs.

GAO reported that heavy use of early-out retirement at Office of Personnel Management -- it runs the program for all government agencies -- virtually eliminated its top career management team, and may have contributed to long delays in getting pension payments to new retirees.

OPM was created by the CS reform act. The law abolished the old Civil Service Commission and replaced it with several new agencies, including the Opm. Many former CSC officials retired early shortly thereafter.

The GAO said that OPM okayed 149 early retirements for itself because of a reorganization. Twenty-one investigators and four claims processors were given early retirement although OPM had -- still does -- a big backlog in retirement claims pending. After the early retirements, GAO said, many of the jobs were refilled with new people.

GAO's report said that a 1979 reorganization at the Department of Energy made wide use of early-retirements with little justification. During an early-out period at DOE, the auditors say, 206 persons retired early. Six were rehired within a month. Thirty-one clerical employes took early retirement and DOE then hired 170 for similar work. Seventeen secretaries retired early and the department then hired 111 new secretaries.

GAO said that early retirements cost $109 million during the 1980 fiscal year, and said that early retirements to date have added more than $600 million to the unfunded liability of the federal pension program. It recommends that Congress, which clearly is in the mood to trim federal retirement costs, repeal the early retirement benefits added by the CS reform act, and force OPM to take a much tougher line in authorizing early-outs when agencies are facing reorganizations or RIFs.