Movies soon may be better than ever for District of Columbia taxpayers.

In hope of adding to the city's economy, Mayor Marion Barry yesterday created a new unit of the city government to promote the production of motion pictures and television programs and commercials. He said it also would help producers cut through the red tape of getting city permits and assistance from government agencies.

Creation of such a unit was proposed last year by the Greater Washington Central Labor Council, which said the move would help provide more jobs locally.

In his announcement, Barry also said more filming in Washington would improve the city's image nationally and encourage tourism.

He said studies show that a quarter to half of a major production company's average daily budget while on location is spent locally on goods and services.

By that standard, he said, the District economy received $3 million from filming of the television series, "Behind Closed Doors," and the movie, "All the President's Men." Crews spent six weeks in Washington on each.

The more recent filming of the Alan Alda film, "The Seduction of Joe Tynan," brought in $50,000. Many scenes purporting to be in Washington actually were filmed in Baltimore and Annapolis.

Other films in recent years with scenes shot in Washington included "The Exorcist," "Advise and Consent," "Hair" and "F.I.S.T."

The new motion picture and television unit will be part of the city's Office of Business and Economic Development. Its only professional staff member initially will be Richard Maulsby, who has been public communications coordinator for the Child Development Associate Consortium.

David Smith, a staff official in the economic development office, said the office receives about one request for assistance each week from makers of films and television commercials.