A Northern Virginia judge has handed prosecutors a setback in their efforts to convict one of the area's largest apartment management firms on charges of failing to report immediately a fire in one of its Arlington high-rises.

Chief Arlington Circuit Court Judge William L. Winston ruled that prosecutors brought the misdemeanor case against the Charles E. Smith Co. in the wrong court. His ruling is likely to force prosecutors to refile the charges against the firm and three of its employes in a lower court.

Winston, in a ruling that prosecutors said they will seek to reverse, held that the charges should have been filed in General District Court, a lower court that has jurisdiction over violations of the county's building and fire codes.

Arlington prosecutor Henry E. Hudson said he probably will ask the judge to reconsider his ruling at a hearing on Wednesday and, if that fails, will take the charges to the lower court.

"Practically speaking this has little effect on the case," Hudson said. "What we wanted to avoid is trying this case twice."

Smith Company attorney Charles Pilzer said Winston's ruling means that if the firm is acquitted in General District Court, then prosecutors cannot appeal the case to the Circuit Court. If the firm is convicted however, it can appeal that decision to Circuit Court, the lawyer said.

Last March the Smith firm, which manages more than 15,000 Washington area rental units in more than 35 residential properties, a property manager and resident manager were indicted on charges of violating the Arlington fire code by failing to report a Feb. 6 fire.

Last month a grand jury indicted a third Smith employe, a desk clerk, on the same charge. The indictments grew out of a blaze at the 12-story luxury Crystal Plaza Apartments in South Arlington, a fire that officials called one of the worst high-rise fires in the county's history.

It did an estimated $1 million damage and injured six firefighters who struggled for 1 1/2 hours to bring it under control.

Arlington officials have said the indictments were sought because they believed it was Smith's policy to first report fires to the company's management, not to the fire department as required by law.

Smith and the three employes have pleaded innocent. If convicted, each faces a maximum penalty of a $1,000 fine and a year in jail.