AN ISSUE OF ELEMENTARY human rights will be on the line today when the Senate votes on H.J.Res. 554, the proposed constitutional amendment to give the District of Columbia full voting representation in Congress. We urged the Senate to approve this measure, as passed by the House, and move the amendment along to the states for ratification.

There is no question that a denial of fundamental rights exists. Even many opponents of H.J.Res. 554, such as Sen. Orrin G. Hatch (R-Utah), acknowledge the unfairness of denying Senate and House representation to about 700,000 citizens on no other grounds that the they happen to reside in an enclave carved out nearly two centuries ago as the nation's capital.

Some senators, though, are still not sure that D.C. representation is the proper remedy. To answer that, it's helpful to consider in what ways the District is - and is not - unique. It is not unique in one fundamental respect: It is inhabited by U.S. citizens who pay federal taxes and are subject to federal law. It is , of course, unique and the sense that it is not "just another city." If it were, it would be in a state; its residents would have the same rights of representation on Capitol Hill that people in Salt Lake City, Oklahoma City and every other American city enjoy.

But the District, the seat of government, is not a state - nor in a state. Why not? The standard explanation is that Congress, sitting in Philadelphia, had been menaced by a band of unpaid soldiers in 1783 and wanted to secure a meeting place whose safety did not depend on state militia or local police. There was another reason, too; as historian Constance McLaughlin Green pointed out, no state wanted the capital to be under another state's direct authority.

The significance of that history is what isn't in it. There's no sign that the founding fathers meant to create a colony whose residents would lack basic civil rights. They were, you might say, in quite the opposite line of work. James Madison, for instance, assumed that the District's residents would have a voice in their local government. The question of a local voice in Congress was just overlooked. That's understandable; it mattered little then, when Washington was a swamp with 14,000 inhabitants, mostly engaged one way or another in the business of government, and Congress was a part-time body with little impact on most people's lives.

As the District's population and Congress's influence have grown, the capital's inadvertent exclusion from Congress has become a gross inequity. There is no need for drastic steps, such as returning most of Washington to Maryland - or, for that matter, moving Congress back to Philadelphia. Such uprootings would be far more disruptive and historically unsupportable than granting the District's residents a fair voice and vote in Senate and House.

H.J.Res. 554 is fully in accord with the national tradition of expanding political liberty. That tradition, over the years, has fostered the enlarging of the union and a vast extension of democratic rights, despite strong partisan and sectional apprehensions at every step. In that spirit, citizens in the District have already been granted local elected government and the right to vote for president. In that same spirit, the pending amendment has gained impressive bipartisan support - including this weekend's endorsements by Majority Leader Robert C. Byrd (D.W. Va.), Minority Leader Howard H. Baker (R-Tenn.) and Robert J. Dole (R-Kan.). Like so many people and groups throughout the nation, they rightly see the votes today as a major test of the Senate's commitment to human rights - at home as well as abroad.