The city was mum about why it doesn't ticket drivers going 6-9 mph over the limit, as allowed. View Full Caption DNAinfo/Benjamin Woodard

CHICAGO — If the point of Chicago's 147 speed cameras is to slow down traffic and prevent crashes, then why isn't the city slapping fines on as many speeders as possible?

That's a question the city never answered while DNAinfo Chicago did an extensive analysis of the city's speed camera program.

The $58 million in fines issued since the program began more than a year ago surprised many Chicagoans, but the city could have issued many more violations than it did.

For reasons not made available — despite repeated requests — the city has not ever issued a violation to drivers speeding between 6-9 mph over the limit, even though it's allowed by law.

The violation carries a $35 fine, but those speeding drivers never got mailed a citation for the violation, according to the Chicago Department of Transportation.

The data, from October 2013 to April 2 this year, give a hint at how much potential revenue the city is missing, considering its very possible the number of drivers going just a few mph (6-10) over the limit is greater than or at least similar to the number nabbed at going 11 mph or more over the limit:

Warning violations: 926,279

10 mph over limit: 135,114

More than 11 mph over limit: 532,746

It's unclear when or if the city will begin ticketing all violators.

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