It's one thing to oppose and to criticize a developer and public officials for actions the critic finds disagreeable. But it's quite something else to use a bootlegged letterhead and photocopied signature of an official to broadcast such criticism.

This has occurred in Washington for the second time in a month. Somebody with a compulsive resentment toward Oliver T. Carr's Metropolitan Square development, around the corner from the White House, has mailed a second officially described "fraudulent" letter and document to a list of recipients.

One copy of the mailing landed Friday on the Metro Scene desk, bearing a 39-cent postage stamp on an envelope bearing the printed return address of the National Capital Planning Commission, a federal agency.

Inside the envelope was an eight-paragraph letter bearing a purported written signature of Reginald W. Griffith, the commission's executive director. Also in it was an official-looking document bearing the commission's imprint that contains the text of a Senate bill that would set building height limits in the suburbs plus the Congressional Record transcript of a Senate discussion of the bill. The bill was provoked by the proposed 52-story PortAmerica tower in Prince George's County.

Although the text and transcript were photocopies from the Record, both the letter and the document as packaged were described as "fraudulent falsifications" by George H.F. Oberlander, acting executive director of the commission in the absence of the vacationing Griffith.

The letter with Griffith's signature is transparently phony since it contains an attack on Griffith himself and purports to acknowledge that the commission staff is meddling to limit suburban building heights while ignoring its own legal role in the city.

Critics of Metropolitan Square have contended that Carr was improperly permitted to exceed usual height limitations, giving the top floors of the building a potentially dangerous overview of the White House.

That's surely arguable, but a court suit against the project failed. And Griffith has said the commission never took a position.

Oberlander said copies of the new correspondence, like that last month, have been turned over to the FBI and postal inspectors for investigation.

"We believe there are laws being violated," Oberlander said. "It's taking time and costing taxpayers money. It's a nuisance." We Scream for Ice Cream!

Hey, all you folks in the White House and the Executive Office buildings, you employes of the Inter-American Development Bank, you staffers of the U.S. Chamber of Commerce, you members of the Metropolitan Club -- in fact, anyone who is near 17th and H streets NW between 12:30 and 1:30 p.m. tomorrow: It's ice cream freebie day again!

As in the past four years, Potomac Grange No. 1 -- made up of employes of the National Grange headquarters at 1616 H St. NW, perhaps the only totally urbanized Grangers lodge in the nation -- is honoring the dairy industry by inviting neighbors to drop by for a free cone. For Metro Scene, spokeswoman Judy T. Massabny promises not a single scoop, but two.