A D.C. Superior Court judge who presided over the case of an 11-year-old Northwest boy jailed last year for hitting a friend with a baseball bat yesterday described prosecution of the boy as "senseless" and said he "didn't hesitate to dismiss it."

"I was just shocked when the case came in," said Judge Nicholas S. Nunzio. "My God. What happened to him shouldn't happen to anyone."

Meanwhile, D.C. Assistant Police Chief Isaac Fulwood Jr. said yesterday he will order an investigation into police handling of the 11-year-old, who was charged with assault and locked in a cell at the court, where on May 24 he was sexually assaulted by two older youths.

Fulwood said an article in The Washington Post describing the incident "raises a whole bunch of questions about the way it was handled." Among them, he said, is whether the case "should have been deferred" to less drastic procedures than being taken to court.

Fulwood said he will assign the investigation to Deputy Chief Leonard Maiden, head of the department's Youth Division, and Deputy Chief James P. Shugart, commander of the 4th District, where the boy was arrested.

Maiden earlier said that juveniles usually are taken to court only as a "last resort" and that about half of all youth offenders arrested are handled with less severe methods, such as counseling.

The Washington Post article detailed events leading to the incarceration of the 11-year-old, who said he was just horsing around with a friend on May 22 when he "accidentally" hit the other boy on the head with a baseball bat.

The injured boy suffered a deep cut in the back of the head and was treated at Children's Hospital. His mother asked the family of the 11-year-old to pay for the hospital bill and became upset when told they had no money, according to the grandfather of the 11-year-old.

The mother of the injured boy complained to police at the 4th District, who charged the other youth with assault with a dangerous weapon and turned him over to deputy U.S. marshals, who placed him in a cell at the courthouse.

There, according to the boy and police, the youth was beaten by a 14-year-old and a 17-year-old and forced to commit sodomy. The boy, who is now 12, was later found to have contracted syphilis.

The two older youths pleaded guilty to charges of sodomy.

"I think the whole thing was precipitated because of a bill," Judge Nunzio said. "Looking back on it, I understand why the police went forward with it and why the corporation counsel went forward with it. You had a citizen demanding that this kid be prosecuted."

Nunzio dismissed the case for "social reasons" three weeks after the boy was arrested, without objection from city prosecutors.

Nunzio said he was "incensed that something like this could happen . . . . We don't hear of everything that goes on down there. But I was shocked."

The boy -- never in trouble with the law -- previously had been treated at Children's Hospital for depression. After the incident he became suicidal and was admitted to the hospital for continuing psychiatric treatment. Last September, his mother died of a bleeding pancreas.

"I think it was an astounding story, just in terms of the impact on the youngster," said D.C. Council member Charlene Drew Jarvis (D-Ward 4). "That is an extraordinary amount of tragedy for an 11-year-old."

Jarvis said she will ask Shugart and Police Chief Maurice T. Turner for a full briefing because of questions she has about the arrest.

Jarvis said she also was puzzled by actions taken by the D.C. corporation counsel's office, which prosecutes juveniles in the city.

The boy was released from the cellblock the day he was arrested when prosecutors did not file a complaint against him in court. Prosecutors filed the assault complaint June 1, days after they learned of the assault.

"I wonder why the charges were filed after the incident," Jarvis said.

Officials of the Marshals Service and the court have declined comment.

Attorney Daniel Arshack has notified the Justice Department of the family's intention to sue for $1 million, claiming that deputies should have protected the boy.

Arshack has also written Mayor Marion Barry suggesting that the city settle out of court.