The federal courts are bearing down on the New York City Police Department’s constitutionally suspect stop-and-frisk program, under which hundreds of thousands of citizens are stopped on the streets each year, often illegally and for no discernible reason. Earlier this month, the federal judge who is presiding over three lawsuits that challenge different parts of the program issued her harshest ruling yet, putting the city on notice that some aspects of stop and frisk are clearly unconstitutional.

The ruling, by Judge Shira Scheindlin of Federal District Court in Manhattan, came in the case of Ligon v. the City of New York. The case was brought on behalf of people who say they were illegally stopped, given tickets or arrested on trespassing charges in private apartment buildings, some of them in buildings where they lived.

The judge excoriated the city for flagrant indifference to the Fourth Amendment. The amendment has been interpreted by the courts to mean that police officers can legally stop and detain a person only when they have a reasonable suspicion that the person is committing, has committed or is about to commit a crime.