A recent shimmering autumn day drew dozens of blue- and white-collar workers into Lafayette Square. Lured by the promise of a lunch-hour respite from pneumatic drills, word processors, telephones and bosses, they opened their quiet conversations, newspapers, sandwiches and books; some stretched their length on the cool grass, took one last look at the reassuring canopy of blue and fell asleep.

It was noon. At 12:03, just as the scene had composed itself for the brush of a Seurat, a fellow equipped with an American flag and an amplifier established himself in the midst of this rare harmony between man and nature. He then harangued all and sundry at a decibel level that startled the pigeons, sent the squirrels scrambling and knocked Andy Jackson's hat askew.

The reaction of the victims was disappointing. Like galley slaves under the lash, they simply turned baleful glances at their tormentor and docilely accepted what has come to be the inevitable in the pocket parks of Washington -- the uninvited lecture. That it was gibberish added no increment to the outrage. The Lord's Prayer or Washington's Farewell Address would have been equally out of place.

A park policeman lounged by the fountain, close enough to save the man from the spontaneous combustion of a smoldering crowd, but not at all near enough or indeed disposed to save the crowd from the man.

I asked the officer if this assault on the privacy of everyone within earshot was legal. He said, "Yes, the man has a permit."

"To speak?"

"Yes."

"With amplification?"

"Yes."

"This much amplification?"

Here the officer's assuredness faded. After a moment, though, he suggested sonic beauty was in the ear of the listener, or words to that effect. At any rate, the by-now scandalous encroachment on the public peace had not aroused his constabulary instincts in the slightest, whereas my inquiries were beginning to.

I left the park deep in thought, pondering the same puzzlements that have occupied the Senate Judiciary Committee in recent days. One of their questions had been well answered. The enhancement of one man's freedom can definitely detract from another's -- in this case, about a hundred others. I recognized the officer of the "peace" was doing his duty as he saw it, and that the way he saw it somehow stemmed from his understanding of applicable law and regulation.

Was he correct? Calling higher police authority for moral reinforcements, I was told of a fascinating procedure that could have been invoked. Upon complaint of a citizen in such cases, the officer notifies headquarters. Headquarters then gets in touch with the Environmental Protection Agency. The EPA then dispatches a specialist to the scene, armed with a sound-monitoring device. Should this aural Geiger counter register "tilt," the offender is warned and, if necessary, restrained.

When asked if this ingenious and efficient procedure had ever been invoked, my source went silent. "Hello?" I said. "Not that I know of," he confessed. What a pity to deny a fun-loving city like Washington the side-splitting pleasure of witnessing -- and timing -- the resulting frolic. The only remaining question is whether the film version should feature Laurel and Hardy or the Marx Brothers.

To return to the subject: during his historic visit to these shores, Pope John Paul made a statement we should take both to heart and to the local precinct: "True freedom," he said, "is the freedom to do what one ought to do." That does imply judgments that invite differences. And should the majority uphold unbridled evangelism in public parks, I withdraw my motion.

Still, I believe that when William Pitt described the parks of his capital city as "the lungs of London," he was referring not to the exhalations at Hyde Park, but to the beneficent return of oxygen to grateful Londoners from their green spaces.

"I love tranquil solitude," said Shelley, "and such society as is quiet, wise and good." That's all the folks that day were seeking in Lafayette Park. Has the great democracy, which drew infant breath in Shelley's time, decided in its manhood that this is too much to ask?

James W. Symington is a Washington lawyer. He was a Democratic representative from Missouri from 1969 to 1977.