On Monday, federal Judge Shira A. Scheindlin ruled that the New York City Police Department's stop-and-frisk practices were unconstitutional, but to thousands of the city's Black and Latino men, that wasn't news.

The real headline for many in New York's Black and brown communities was how attorneys convinced a federal judge that the city had violated the Constitution by engaging in years of racial profiling. The answer to that riddle can be found largely in one place: data crunched by Jeffrey Fagan, a Columbia University professor whose research has now made long-standing complaints of millions of Black and Latino men an objective reality.

Scheindlin relied heavily on a pair of painstaking researched studies by Fagan, who is a criminologist. One study addressed the plaintiffs' concerns that the police practice violated the Fourth Amendment, which protects against unreasonable searches; the other that stop and frisk violated the 14th Amendment's protections of equal protection under the law for all Americans. "The city adopted a policy of indirect racial profiling by targeting racially defined groups for stops based on local crime suspect data," Scheindlin wrote, to the chagrin of city officials. It was Fagan's two studies that largely led her to this conclusion.