MAYOR WALTER WASHINGTON has needlessly raised questions of propriety-if no legality-by removing to his home almost 200 plates, statues, medals, photographs and other gifts from foreign dignitaries acquired during his 11 years at City Hall.

No one knows whether those mementos, until recently on display outside the mayor's office, were gifts to the city or to the mayor personally. More important, nobody has a complete list of these gifts-or any reliable appraisal of their value.

According to State Department regulations, federal and District employees cannot personally accept gifts valued at more than $100 from foreign governments. Gifts valued at more than $100 must be registered with the State Department and turned over to the federal government after a "reasonable" period of time. But a statement acknowledging receipt of even those items that the mayor himself says are worth more than $100 has never been filed with the government.

The mayor sounds downright irritated that anyone would question the matter. He says that only items of personal significance have been removed; they will eventually be displayed in his home. State Department officials are understandably reluctant to press the case-they are not inclined to request an itemized statement of gifts, and they have no intention of asking him to open his home for inspection. So there the matter rests-or may rest, depending on the tax implications of the mayor's memorabilia. It is just possible that the Internal Revenue Service might have an interest in requesting an audit or appraisal of the mayor's acquisitions from foreign admirers.

Whether the mayor has broken the law or only substantially bent it is not for us to decide. What strikes us as certain, however, is that the city ought to have some standards on such matters. It may be that, in keeping with the spirit of home rule, the federal regulations should not apply to the District; other major cities are not covered by the State Department's rules. In New York City, for example, the mayor is allowed to keep items that have been given to him personally. Gifts to the city go on display in city hall and eventually may be sent to a museum or library. That's a logical and appropriate way to handle the matter. While it may not be the most important reform now needed in the city's management, perhaps Mayor-elect Marion Barry should consider proposing some such system to the City Council once he takes office.