Story highlights A new law caps how much money local governments can collect from traffic tickets

It comes after a Justice Department report found such methods were used to generate revenue in Ferguson

Governor calls it "landmark legislation"

(CNN) Missouri cities can no longer treat their citizens like ATMs, a lawmaker said Thursday as the state's governor signed a bill capping how much money local governments can collect from traffic tickets and fines.

"For people who have lived in these communities that fear they are going to be pulled over and harassed because that city needs money, that's going to change," said Republican state Sen. Eric Schmitt, who sponsored the bill, told reporters.

The federal investigation came after the shooting of Michael Brown in Ferguson last August sparked allegations of excessive police force and bias against African-Americans.

"Many officers appear to see some residents, especially those who live in Ferguson's predominantly African-American neighborhoods, less as constituents to be protected than as potential offenders and sources of revenue," the probe concluded.

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