A Columbia Scholar at the Center of New York's Landmark Stop-and-Frisk Ruling

Fagan, an expert witness for the plaintiffs, analyzed nine years of New York Police Department data that the plaintiffs used to demonstrate that the stop-and-frisk program was riddled with constitutional violations.

He developed complex statistical models to show that blacks and Latinos were significantly more likely to be stopped than whites. His report found that racial disparities in stop rates were present even after adjusting for factors such as crime rates, local social conditions and police concentration in neighborhoods. He also reported that the NYPD used constitutionally questionable rationales in deciding whom to stop. Fagan’s analysis showed that NYPD officers were relying on stylized ‘scripts’ to characterize why they stopped New Yorkers, rather than expressing the individualized suspicion that the constitution demands.

In her 198-page ruling (PDF), U.S. District Judge Shira Scheindlin (GSAS’69) wrote that she found Fagan to be a more reliable witness than the city experts defending the practice. “Dr. Fagan has a deeper understanding of the practical, real-world meaning and implications of the statistical analyses in this case.”

Not surprisingly, Fagan praises the judge for her ruling. “Her sense of the historical arc of the stop-and-frisk phenomenon suggests a deep understanding of the institutional culture both of the NYPD and its political context,” he told "The Record." Her order that the city appoint a monitor to ensure that the city abides by her decision is “a balanced proscription to correct a longstanding practice of constitutional and policy overreach by the NYPD.” Mayor Michael Bloomberg and Police Commissioner Raymond Kelly strongly defend the NYPD’s crime prevention tactics, and the city intends to appeal the ruling.

Fagan, whose Ph.D. is in policy science, has spent his career researching criminal justice and capital punishment and published scores of articles, studies and books. He joined Columbia from Rutgers University in 1996 as a professor in the Department of Epidemiology at the Mailman School of Public Health. Although he is not a lawyer, Fagan joined the law school faculty in 2001, where he is the Isidor and Seville Sulzbacher Professor of Law and director of its Center for Crime, Community and Law.

The stop-and-frisk case, "Floyd vs. City of New York," was filed in 2008 by the New York-based Center for Constitutional Rights. “We knew when we started this case in 2008 that he was the leading scholar in the country on this, and we wanted him to be a part of this,” said Darius Charney, a senior staff attorney at the center and one of the trial’s lead attorneys. Charney added that without Fagan’s research, “I don’t think we could have won the equal protection claim that was a big part of the case.”

The Floyd case is not the first time Fagan has analyzed NYPD stop-and-frisk practices. In 1999, he and a Columbia team of faculty and students were retained by then-Attorney General Eliot Spitzer after NYPD officers shot and killed Amadou Diallo, an unarmed immigrant who died in a hail of 41 bullets after putting his hand in his jacket to take out his wallet after police stopped him.

Fagan and his team from Columbia Law School did research to determine whether the practice violated the 14th and 4th amendments. Working with Professor Andrew Gelman from the departments of Political Science and Statistics, their analysis was the basis for the Spitzer report’s conclusion that there was a strong correlation between race and the likelihood of being stopped, even after adjusting for crime.

“Despite a strong report from the attorney general on how to remedy the exact same situation, nothing really changed,” Fagan said, adding that he was a little reluctant to take up the same research nearly a decade later. Fagan is continuing to analyze the data on stop-and-frisk but his research isn’t final.

Charney, speaking for many, says that Fagan’s involvement was crucial. “He’s the guy. His work on our case was critically important.”