Members of Congress awarded themselves a wonderful bonus at the end of last year's session. In the true spirit of balancing the budget, they voted themselves a series of tax exemptions for allegedly work-related expenses that would knock your eyes out if they showed up on your income tax forms.With the friendly cooperation of the Internal Revenue Service, which last week issued guidelines on the new rules, it is now possible, even probable, that members of Congress will pay next to nothing in taxes on their congressional salaries.

They will be allowed to take as tax deductions the cost of owning or renting second homes in Washington, home maintenance costs, laundry costs, utility costs and work-related telephone costs, and travel costs outside of Washington. They will be allowed to deduct food and household help costs. The liberal formula announced by the IRS allows members of Congress to deduct $75 in expenses, without itemizing them, for every day Congress is in session. There were 241 congressional days in 1981, which comes out to a neat $18,075 in unauditable expenses. Those who spend more can deduct it, but they have to itemize. The congressional bonus, incidentally, is retroactive to 1981, which means the immediate loss of something like $9.6 million of taxable income to the federal treasury.

Members of Congress start out with a taxable salary of $60,662.50. If you throw in all of the other deductions American citizens get, such as interest payments on car and home loans, charitable deductions, exemptions for children, dues to professional associations and so forth, it is easy to see how there may be an elite corps of lawmakers who won't pay taxes at all.

This, I submit, is an outrage. My heart goes out to anyone who has to maintain the cost of a first home in Washington, let alone a second home, but if members of Congress are feeling strapped they ought to give themselves a pay raise instead of a series of underhanded tax loopholes. (This, in the true spirit of legislative reform, was tacked onto a bill restructuring the black lung program.) There are very clear IRS rules about what is and what is not a legitimate business expenses, and what you can deduct for travel and living costs. They are the rules that all the other out-of-towners residing here live under.

The ultimate in tackiness for this episode has to be the legislators' inclusion of their laundry costs as a business expense. Do the members of Congress clean their clothes just because they are members of Congress? If they were in some other line of work, would they -- heaven forbid -- not do their laundry?

The self-indulgent tax dodging at work here is all the more striking if you compare what business expenses Congress and the IRS allow the rest of the American people. You cannot, for example, deduct the cost of driving your car to and from work, or the maintenance and insurance on it. You can't deduct the cost of working clothes, not to mention your laundry costs (I am assuming most of us do launder our clothes even if we aren't members of Congress), or the costs of maintaining an office in your home where you can work at nights or on weekends. You certainly can't deduct your utilities or your food or your household cleaning help.

The same Congress that thinks its laundry costs are justifiable work-related expenses is of a much more penurious mind when it comes to something that really is work-related, such as child care. The same legislators who granted themselves an $18,000-plus deduction for "business expenses" made the grand gesture of raising the child care credit for working parents this last session by a total of about $160. In 1982, the most you probably can take off for child care on your income tax bill is a $960 tax credit, up from the previous maximum of $800, for two or more children. This is nowhere near the amount many people spend on child care, but efforts to deduct all of people's child care costs historically have gotten nowhere in Congress. Yet for millions of working parents, at least one income would not be possible if the wage-earner were not also spending thousands on child care. If that is not a legitimate work-related expense, and a socially useful tax subsidy, then I do not know what is.

I do know that the laundry is not.