Think New York City’s stop-and-frisk practices were bad? Check out Chicago’s police stops.

Police stops were more common in Chicago last summer than they were at the height of New York City’s controversial “stop-and-frisk” practices in 2011, according to a new report from the American Civil Liberties Union of Illinois.

Chicago police made more than 250,000 stops that did not lead to arrests between May and August 2014, disproportionately impacting African Americans, according to the report. Chicago’s rate of street stops in those months was more than four times New York City’s in the summer of 2011.

“What this data shows should be a wake-up call for residents of the city,” Karen Sheley, senior legal counsel at the ACLU and one of the authors of the report, said in a statement. “CPD is engaging in wholesale stop-and-frisks of African-American youth, without any link to criminal activity in most cases.”

This data may even understate the number of stops in Chicago, since police in the Windy City only recorded stops that didn’t lead to arrests or tickets. But the data also doesn’t show how many stops resulted in frisks, so not all the stops were necessarily like New York City’s stop-and-frisk searches, which drew national attention for their disproportionate use against black New Yorkers.

Black Chicagoans were similarly much more likely to be victims of the stops, according to the report. Although black residents make up nearly 33 percent of the city’s population, they accounted for 72 percent of stops. These disparities were more pronounced in white neighborhoods like Jefferson Park, where black Americans were more than 21 times as likely as their white counterparts to be stopped, after accounting for the neighborhood’s white and black populations.

A federal judge in 2013 ruled New York City’s stop-and-frisk practices unconstitutional because they unfairly impacted African Americans. Violent crime and robberies fell in the year following the ruling, even as police were forced to reduce stops.

The stops are legally allowed when police have a reasonable suspicion that a person has been or will be involved in criminal activity. But the ACLU found that Chicago police often didn’t appear to meet this standard: officers failed to give a legally sufficient reason for stops in half of the randomly sampled contact cards filled out in 2012 and 2013 after stops.

The ACLU recommended policy changes to require better training for stops, prevent the practices’ disproportionate racial impact, and better track who’s affected by the stops and why. Without any changes, Chicago could potentially face the type of legal threats New York City and other cities dealt with before courts and the US Department of Justice stepped in to mandate reforms in police stops.

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