The Montgomery County state's attorney's office filed new misdemeanor charges yesterday against a 19-year-old Rockville man accused of setting a fire in the shape of a swastika in July on a Jewish neighbor's lawn.

The filing of new charges against John F. Finnegan III of Duke Street came 10 days after the original charge against him was dismissed, a move that had upset the victims of the vandalism. The original charge, arson of personal property, did not apply in Finnegan's case because legally grass is real property, not personal property, District Judge Stanley Klavan ruled Aug. 25 in dismissing the charge.

"The judge was perfectly proper in his decision," Deputy State's Attorney Matthew Campbell said yesterday. This time Finnegan, who has pleaded not guilty, has been charged with malicious destruction of property and with violating a county ordinance that prohibits the setting of a fire "on someone else's property without obtaining that person's permission," Campbell said.

The owner of the home where the July 15 incident occurred said yesterday that it especially disturbed his wife, who was born in Colombia after her family fled Nazi Germany in the mid-1930s.

The husband, a Roman Catholic, who spoke on the condition that he not be identified, said he was in Klavan's courtroom Aug. 25 and was embittered by the judge's ruling on the arson charge. He said he was gratified by the new move to prosecute Finnegan.

The malicious destruction charge, which covers both real and personal property, carries a maximum sentence of three years in prison and a $2,500 fine, Campbell said.

Finnegan could not be reached yesterday, but his attorney, William F.X. Becker, said, "It will be our position that they're precluded from doing this under the double-jeopardy provisions of the Constitution."

Finnegan and a companion, Gary Stein of Gaithersburg, allegedly wrapped a car in the family's driveway with toilet paper early the morning of July 15 before Finnegan allegedly poured gasoline in the shape of swastika on the front lawn and set it afire.

At Finnegan's first trial, Stein, who is Jewish, testified that he ran to a nearby yard after helping wrap the car with toilet paper and, looking back, saw an orange glow, according to Campbell. He said Stein also testified that Finnegan had been carrying a gas can.

He testified that he learned later about the swastika, felt sorry for the family, surrendered to police and identified Finnegan.

Campbell said Stein, 19, has agreed to perform 80 hours of community service in return for not being prosecuted.