If the court case filed against "Ronald Reagan, et al." by the Community for Creative Non-Violence were to be decided on architectural merits, the federal government wouldn't stand a chance.

At issue is the future of the shelter for the homeless in downtown Washington, an ugly, ramshackle rat trap nobody would miss if there seemed to be a decent alternative for the 2,000 or so unfortunate folk who use it during a typical cold winter month.

The feds want to close the building and evict its temporary tenants. The CCNV wants to keep it open. Early this month, before its unfortunate change of heart, the administration presented a plan of sorts to renovate the sorry structure. This was done in response to the CCNV's imaginative architectural plans for the shelter, unveiled early this year and presented to the government in March.

There are, of course, issues other than architectural ones involved in this unseemly fight. The mistrust is almost palpable between the administration and the CCNV, the tiny band headed by Mitch Snyder. The government, as governments will, clearly distrusts a bootstrap operation run with just a few rules and no bureaucrats, while the CCNV wants the government to pay for the renovation and then clear out. Costs are, as always, a concern.

But if ever there was an argument about social policy to which architecture is absolutely central, if ever there was an example of human good that good design can do, this is it. The administration's so-called plan for the shelter -- three sheets of paper showing the most minimal disposition of various functions -- is as stupid and brutish as the CCNV documents are intelligent and humane. The CCNV perspective is to see the problem as a challenge and an opportunity. The administration's hapless effort amounts to no more than a dispirited wish that the problem would go away.

Let's look at the particulars. The three-story building at 425 Second St. NW, constructed during the 1940s as a wartime "temporary," is a wretched thing suffering from years of neglect. The roof leaks badly. The boilers are in desperate need of repair. Most toilets don't work. Hot water is a sometime luxury. One would say that the building is uninhabitable except that, even during the summer, several hundred people with no place else to go sleep there every night.

Except for basics such as roof repair, the administration's proposal represents no improvement at all in these deplorable conditions. In many ways it would make them worse. It violates, for instance, a cardinal rule of the shelter world, which is to keep homeless men and women as far away from each other as possible. Today entrances for males and females are separated by close to a city block. In the administration's proposal men and women eat together and enter the same doors.

But then, the plan violates common sense as well as elementary rules of good architecture. It locates the kitchen nearly 250 feet from the loading dock. It places one major entrance on a dark alley. It locates some service facilities on one side of the building and others on the other side, providing no connecting link. It puts the women's "drop-in" center -- a place for homeless people to gather during the daytime -- in the dead, windowless center of the structure. It makes no provision at all for the temporary storage of a person's belongings. The list could go on, but why bother?

The central, philosophical difference between the two plans is the idea of vast open dormitories sleeping up to 250 persons, which the administration proposes, versus the individual, doorless, cubicles grouped in a "village" pattern, as foreseen in the CCNV plan. Whether individual rooms are desirable for all or even most of the guests is debatable, but common sense, as well as a goodly concern for one's fellow man, would seem to indicate that a degree of privacy is necessary to an individual's sanity and self-respect, as well as for a good sleep.

The CCNV plan was prepared by a group of five advanced architecture students who worked at the shelter through the month of January under the guidance of architects Conrad Levenson and Alan Feigenberg of New York. It may not be perfect -- the paradoxical problem of housing the homeless has received little architectural attention -- but it is, demonstrably, efficient.

It proposes, for instance, a centrally located kitchen from which hot food could be commodiously dispatched to the five semi-autonomous residential areas, each with its own dining room, lounge and "quiet area." It places related services -- medical facilities, employment and housing counseling, laundries, toilets, shower rooms and so on -- in clusters accessible to each other and to clearly articulated entrances. It provides for isolation rooms for men and women who refuse to be deloused. It separates men from women and locates their drop-in centers at the edges of the building (where, after all, the doors and windows are).

It should be emphasized that we're not talking luxury here -- we're talking cheap materials and bare-bones essentials. Those proposed cubicles, for instance, occupy all of 42 square feet. And we're talking ingenuity and intelligence -- how to do a lot with a little.

Indeed, a careful look at these architectural plans calls into question the common assumption (and perhaps the only one the administration and the CCNV share at this point), that, as Snyder says, "nobody likes large shelters, everybody would prefer smaller, community-based facilities."

Given the massive need, there are clear benefits, economic as well as social, in the strategy of putting major services for the homeless in one large location. There are obvious benefits, too, in building upon the loose, self-help social structure that the CCNV has established at the shelter, rather than just throwing this valuable experience away.

Doubtless the CCNV plan could be improved. But it is the best architectural work that has been done so far on an intransigent problem, and it fulfills the spirit of a pledge the administration made, under direct instruction from President Reagan (and after a hunger strike by Snyder), two years ago. This was "to create a model physical shelter structure to house the homeless in the District of Columbia as long as a critical need exists, with special attention to preserving (their) dignity . . . "