A newly proposed federal policy to keep future memorials off the National Mall and disperse them elsewhere within the city is being considered for adoption. It's a capital idea I urge the public to support.

But I am not a disinterested or neutral observer.

Testifying at a congressional hearing 13 years ago, I strongly advocated passage of the 1986 Commemorative Works Act, which limited memorials on the Mall to those of national, lasting significance and required that all proposed memorials and memorial sites be reviewed and approved by Congress.

Since 1986, I have written several times in The Post about Washington's memorials and sounded warnings about the risks of filling up the Mall. Three years ago, I joined many others in questioning the appropriateness and size of the World War II memorial site, the memorial program for the site and the initial, competition-winning design responding to that program.

I am a member of a team of volunteer consultants advising the Joint Task Force on Memorials--the National Capital Planning Commission (NCPC), the National Capital Memorial Commission and the Commission of Fine Arts--in formulating these new policies and plans for memorials and museums.

I am disclosing all of this to make sure that readers understand my bias.

The task force is proposing something conceptually simple: the creation of three distinct commemorative zones at and around the capital city's heart.

* The Reserve. No new memorials, other than those already approved, would be permitted within the principal Mall areas of the monumental core. The Reserve would encompass the great open spaces along the east-west cross-axis between the Capitol and Lincoln Memorial and the north-south axis between the White House and Jefferson Memorial, including the Tidal Basin shoreline.

* Area A. Future memorials of "preeminent significance" could be built in areas immediately adjacent to the Reserve. They would be "subject to restrictive criteria and design guidelines ensuring that memorials do not intrude on the significance of the setting." Area A includes the Federal Triangle, the blocks between the Mall and Maryland Avenue SW, Theodore Roosevelt Island and the federal parklands along both sides of the Potomac River from the 14th Street Bridge to the Key Bridge.

* Area B. Anywhere else in the city would be available for memorials of "lasting historical significance," although the policy statement emphasizes "the important North, South and East Capitol Street axes, circles and squares on major avenues, waterfronts, urban gateways and scenic overlooks."

The Joint Task Force's proposed policy reflects fundamental concepts embodied in the NCPC's recently completed vision for the city, titled "Extending the Legacy: Planning America's Capital for the 21st Century."

Continuing the tradition of the L'Enfant plan and the even grander "City Beautiful" aspirations of the McMillan Commission plan, the NCPC Legacy plan postulates an entirely new, monumental north-south axis extending southward from the Capitol to the Anacostia River. This axial space would constitute the future venue for new museums, grand civic buildings and memorials to be created during the 21st century and beyond.

In delineating the new South Capitol Street axis, the Legacy plan recognizes that the existing Mall cannot accommodate more museums or other important structures. It also recognizes the need to safeguard the unique visual and historic qualities of the monumental core landscape.

"Although the present Mall departs in many respects from the L'Enfant and McMillan plans," notes J. Carter Brown, chairman of the Commission of Fine Arts, "the essential vision of those plans--defined spaces, long open axes and dramatic vistas--must be rigorously protected."

The Legacy plan also advocates placing future commemorative works at strategic sites throughout the city, not just on or near the Mall. The rationale is compelling. Appropriately sited and well-designed memorials can serve as both symbolic and visual urban landmarks, drawing tourists more deeply into the fabric of the city and catalyzing physical and economic development of city neighborhoods in need of revitalization.

Despite the logic of the NCPC Legacy plan and the proposed task force policy on memorials, some will question the notion of excluding any further memorial building on the existing Mall. Every memorial sponsor naturally tends to believe that the subject of its initiative possesses sufficient national significance to justify commemoration at a site on or near the monumental core. Being told to go elsewhere seems like second-class treatment.

Therefore, part of the challenge for the Joint Task Force is convincing the American public that meaningful memorials in great cities do not have to be at the urban center. It must point to other great capitals--Paris, London, Rome--where memorials abound but are distributed across the cityscape, occupying and energizing strategic sites throughout the urban fabric.

Fortunately, the Joint Task Force is committed to selling this idea. In the interest of encouraging citizen participation, it is hosting public meetings to present its commemorative-zone policies and plans and solicit public comments; the initial meetings will be held Wednesday afternoon and evening, Sept. 29, at the Martin Luther King Memorial Library.

But perhaps the task force, to make its case most convincingly, should conduct public meetings in other cities as well. It is visitors to Washington who live in other parts of the United States, not residents of the capital, who are likely to be the least reserved in questioning the Reserve.

Roger K. Lewis is a practicing architect and a professor of architecture at the University of Maryland.