WITH crocodile tears and self-righteousness, members of Congress periodically find ways to increase their own salaries and benefits while complaining about other federal salaries in general and shortchanging certain civil servants in particular. So it is again in the Senate, where 78 members have found another occasion to be tightfisted on the one hand and loose with the change on the other: having already taken their usual election-year stance of freezing their own pay, these senators voted to deny raises to one group of more than 30,000 federal workers while leaving untouched President Carter's election-year proposal of 9.1 percent increases for the vast majority of the government's white-collar workers.

The result is a mess. However much you think the federal rank and file deserve in the way of a pay raise come Oct. 1, people in the top federal-executive categories -- whose pay is always linked in one way or another with congressional raises -- are getting unfairly squeezed. Not only have their salaries been artificially restrained over the years, but this freeze at the top keeps pushing more and more federal employees against the pay ceiling and toward a government of too many chiefs.

Some of the chiefs, of course, get discouraged and find more satisfying situations in the private sector. It isn't that all federal workers necessarily deserve some debatable form of "comparability" with whatever their alleged counterparts in private business are taking home, even though this is the vague requirement on the books and up to the president to interpret; nor should it be indelibly stipulated that all government employees up and down the line should be hermetically sealed from the effects of inflation in a way that their rank-and-file counterparts are not.

But instead of coming up with a sensible and equitable pay formula for the whole range of federal jobs, the White House and Congress combine to create an unfair pay system that tends to be at once excessive and regressive -- and that only serves to tarnish further the general public's image of federal servants.