CHICAGO (CBS) — The Chicago Police Department and the American Civil Liberties Union have reached a groundbreaking deal to set up an independent evaluation of police “stop and frisk” procedures, in an effort to prevent racial profiling.

The move comes after the ACLU of Illinois in March found Chicago was among the nation’s leaders in the use of “stop and frisk” tactics, outpacing even New York. An ACLU report found police disproportionately targeted African Americans, while the justification for the stops often failed to meet constitutional standards.

“Over 70% of those people are African Americans, but African Americans only make up 32% of the population of our city,” ACLU Illinois legal director Harvey Grossman said at the time.

The study concluded police were far more likely to stop and frisk people in predominantly black neighborhoods. Even in white neighborhoods, blacks were far more likely to be targeted, the ACLU said.

“In Jefferson Park, African Americans make up approximately 1% of the population, but we see that they are stopped at 15 times their presence,” Grossman said.

Effective immediately, the agreement between the CPD and the ACLU calls for retired federal judge Arlander Keys to provide public reports twice a year on police investigatory stops and pat downs, and examine whether they meet legal and constitutional requirements. Keys also is authorized to recommend changes to police policy.

Further, police officers must fill out contact cards any time they make an investigatory stop. The cards will document if the officer conducted a pat down; what, if anything, was found; and if the person was arrested, issued a warning or citation, or if no action was taken. The cards will include the name and badge number of the officer, the race and gender of the person stopped, the reasons for the stop, and the reason for a pat down.

That data will be shared with the ACLU and Keys, who will evaluate whether those stops were based on “reasonable suspicion of criminal conduct.”

“I think this is going to change the way that police officers document stop and frisks. It’s going to ensure that there’s an independent review of whether or not they’re complying with the law,” ACLU attorney Karen Sheley said Friday.

All 12,000 officers on the force also will be required to undergo additional training on the proper use of investigatory stops.

“I got to tell you I’m pleased with the results,” Police Supt. Garry McCarthy said of the agreement. “I’m hoping that this is going to set the standard for how this stuff moves forward nationally. I’m confident that we’re making our stops in a constitutional fashion.”

The ACLU said this is the first agreement of its kind in the nation with this level of oversight, and achieved without litigation.