CHICAGO — Gangs long have been a problem in the Northwest Side neighborhood that feeds into Carl Schurz High School.

But the principal had an unorthodox way of going after them, according to a recently filed federal lawsuit.

She allegedly paid students to give up the gang affiliations of classmates.

“The school is loaded with gang bangers,” said Sally Chiodo, one of four plaintiffs in the lawsuit, which describes her as a former treasurer and secretary at Schurz.

Before leaving as principal earlier this year, Mary Ann Folino would approach two particular students when she needed information, ask them to “identify certain gang bangers,” and pay them $50 per tip — with school funds, Chiodo said.

“That would happen on a regular basis,” she said.

Folino, who could not be reached for comment, may have had good intentions, Chiodo said. She allegedly used the information to try to force out problem students. But it still violated school district policies, the lawsuit contends.

The suit was filed in May by four current or former Schurz employees: a special education teacher, a social worker and an English teacher, in addition to Chiodo.

The complaint targets Folino, the Chicago Board of Education and Chicago Public Schools CEO Ron Huberman, and makes a host of other allegations, including that Folino “engaged in the practice of ghost student enrollment,” in an apparent attempt to boost funding.

The suit also outlines troubles in the special education program, claiming that audit information provided to the Illinois State Board of Education was falsified. (The state board now is looking into this claim, an official said.)

The four plaintiffs complained about various problems at the school, the suit alleges, but “Folino took retaliatory action” against them, violating whistleblower protection rules.

In one instance not outlined in the lawsuit but relayed by Chiodo, a teacher friendly with Folino “blew a gym whistle in my face and said, ‘Tell me you’re not the whistleblower,’” then tossed a bag on Chiodo’s desk with a plastic rat inside.

The Chicago Public Schools’ inspector general’s office investigated that claim and recommended discipline against the teacher accused of wielding the whistle and rat, records indicate.

A CPS attorney who said she is representing Folino declined to comment on the suit, saying: “We do not discuss pending litigation.”

Huberman’s press secretary, Monique Bond, said: “We’re certainly concerned any time allegations as strong as these surface.”

She declined further comment.

The school, located at Milwaukee and Addison, has roughly 2,300 students.

Patrick Rehkamp is a reporter for the Better Government Association

>> Read the partner story at CBS2Chicago.com