That includes a district attorney whose policies have contributed to a decline that extends over his long tenure, defense lawyers who exploit delays at every turn to help their clients beat charges, judges who are unable or unwilling to take command of their courtrooms and court administrators who overlooked the growing crisis while refusing requests for more resources. All of this happens in the poorest borough in the city, a place lacking the political clout to stir outrage and force reform.

Months of court visits in the Bronx beginning last June — which included observations of trials, examinations of case files and transcripts in scores of cases, analyses of law enforcement statistics and reports, and dozens of interviews with crime victims, witnesses, defendants, lawyers, court officials, judges and jurors — showed the broad range of problems afflicting the borough’s justice system.

For years trials have been postponed every week because there were not enough judges. But less compelling reasons are also sufficient, including prosecutors’ vacation plans and defense lawyers’ birthdays. Even excuses like a backache and a picnic were deemed sound enough to keep the courts waiting.

Prosecutors from the office of the Bronx district attorney, Robert T. Johnson, routinely tell defense lawyers handling two- and three-year-old cases that they are too new to be dealt with. Two years ago, a judge threw out all charges against a man accused of trying to murder a police officer simply because prosecutors had allowed too much time to pass.

At the same time, the court day is shrinking. It is at best a modest 9:30 a.m. to 4:30 p.m., with an hour for lunch. In practice it has been whittled further because even the most basic functions, like bringing prisoners to courtrooms, are undermined by cascading delays.

In the midst of The New York Times’s reporting, the top official in the state court system publicly acknowledged the “glaring problems” in the Bronx criminal courts, which he said went back “as long as I can remember.” In a January speech, the official, Jonathan Lippman, the state’s chief judge, called the court delays “intolerable,” “entirely unacceptable” and “singularly intractable.”

Concerns about an overburdened, underfinanced court system have nagged with increasing urgency across New York City. The number of felony cases citywide that exceed the courts’ own guidelines for excessive delay — 180 days in most felony cases — has more than doubled since 2000, even as the total number of felony cases has dropped by nearly a quarter.