THE SENATE Judiciary Committee has approved and sent to the Senate floor a proposed constitutional amendment that is at best at Tinkertoy and at worst a disaster. The amendment purports to prevent the federal government from running financial deficits except in certain situations and to make the federal government pay the bills for any actions Congress requires the states to take.

Whether the amendment would actually accomplish these things is a matter of conjecture. Its language is wide open to interpretation, as all constitutional language is, and the final arbiter would be the Supreme Court. Would the justices understand these words the same way their congressional sponsors do? The text of the amendment is printed "For the Record" on this page today.

Take Section 1. With the exception of the limit on deficit financing, it expresses the idea embodied in the existing budget act. By law, Congress is already required to adopt, before October, a statement of receipts and outlays; it has barred itself from appropriating more dollars than authorized in that statement. As the fiscal year unfolds, Congress can always amend that original statement. Would the proposed amendment simply put these existing procedures into concrete? Or would it remove Congress' flexibility? If the latter, what if the interest rate on the national debt suddenly skyrocketed? Would the government be forbidden to make its interest payments or would the president have to cut, say, military pay to find the money? Who knows?

Section 3 is just as convoluted. It says Congress "may not require" the states to engage in "additional activities" without paying the bills. Presumably this means that if Congress decided to standardize the time period during which the polls are open for presidential elections, it -- not the states -- would have to foot the bill. But suppose Congress, as it has done on welfare, Medicaid and highways, chose to make that standardized time period optional -- by offering to pay 75 percent of the costs if a state decided to participate. Would such a law be considered to require state action and thus trigger the amendment's sanctions? And what would those sanctions be -- a lawsuit filed by the states in federal court against the federal government?

These do not exhaust the legal traps we see in the proposed amendment; we do not deal here with its basic thrust, the effort to write economic policy into fundamental law. What, for example, is the "national income"? Does the phrase "all outlays of the United States" include the spending of TVA and the loan guarantees issued by several federal agencies? Does Section 2 make any sense at all, since it says that revenues can't go up faster than the national income unless Congress says they can?

This kind of tinkering with the Constitution is a highly dangerous game. If the proposed amendment means, as its sponsors seem to believe, something quite specific, its history (if ratified) is likely to resemble that of the Prohibition amendment -- troublesome and short-lived. If, as we believe, it is so broadly drawn that no one will know what it really means until the Supreme Court finally interprets it, it could well shift an inordinate amount of economic power from Congress to the justices. The third possibility, of course, is that the amendment doesn't really mean anything. In that case, it doesn't belong in the Constitution, or even on the floor of the Senate. Its authors should put the parts of this thing back in the toy box.