By Monica Davey, nytimes.com
In this city’s urgent push to rein in gun and gang violence, the Police Department is keeping a list. Derived from a computer algorithm that assigns scores based on arrests, shootings, affiliations with gang members and other variables, the list aims to predict who is most likely to be shot soon or to shoot someone. Shaquon Thomas was on it.
His first arrest came at age 13, and others quickly followed, his face maturing in a progression of mug shots. By 18, Mr. Thomas, who was known as the rapper Young Pappy, had been wounded in a shooting, the police said. Then, last May, Mr. Thomas, 19, was fatally shot in what the police said was a running gang feud. His score was more than 500, putting him near the top of the Chicago Police Department’s list.
“We know we have a lot of violence in Chicago, but we also know there’s a small segment that’s driving this stuff,” Eddie Johnson, the police superintendent, said in a recent interview.
The authorities hope that knowing who is most likely to be involved in violence can bring them a step closer to curtailing it. They are warning those highest on the list that they are under intense scrutiny, while offering social services to those who want a path away from the bloodshed.
About three years into the program and on a fourth revision of the computer algorithm that generates the list, critics are raising pointed questions about potential breaches to civil liberties in the creation of such a ranking. And the list’s efficacy remains in doubt, as killings and shootings have continued to rise this year.
In a city of 2.7 million people, about 1,400 are responsible for much of the violence, Mr. Johnson said, and all of them are on what the department calls its Strategic Subject List.
So far this year, more than 70 percent of the people who have been shot in Chicago were on the list, according to the police, as were more than 80 percent of those arrested in connection with shootings.
In a broad drug and gang raid carried out last week amid a disturbing uptick this year in shootings and murders, the Police Department said 117 of the 140 people arrested were on the list.
And in one recent report on homicides and shootings over a two-day stretch, nearly everyone involved was on the list.
“We are targeting the correct individuals,” Mr. Johnson said. “We just need our judicial partners and our state legislators to hold these people accountable.”
Many government agencies and private entities are using data to try to predict outcomes, and local law enforcement organizations are increasingly testing such algorithms to fight crime. The computer model in Chicago, though, is uniquely framed around this city’s particular problems: a large number of splintered gangs; an ever younger set of gang members, according to the police; and a rash of gun violence that is connected to acts of retaliation between gangs.
Supporters of Chicago’s list say that it allows the police to focus on a small fraction of people creating chaos in the city rather than unfairly and ineffectively blanketing whole neighborhoods. But critics wonder whether there is value in predicting who is likely to shoot or be shot with seemingly little ability to prevent it, and they question the fairness and legality of creating a list of people deemed likely to commit crimes at some future time.
“We’re concerned about this,” said Karen Sheley, the director of the Police Practices Project of the American Civil Liberties Union of Illinois. “There’s a database of citizens built on unknown factors, and there’s no way for people to challenge being on the list. How do you get on the list in the first place? We think it’s dangerous to single out somebody based on secret police information.”