Here's a good reminder of why journalists should always double check the data before running with the government's interpretation of it:

Chicago's become infamous for being home to the nation's largest network of the cursed cameras, with 350 in total doing the devil's work throughout the city's intersections. Mayor Rahm Emanuel's been a big booster of them as well, with studies posted to the city's website touting the program, according to the Chicago Sun-Times:

Data posted to the city's website indicate that crashes at red-light camera intersections decreased 33 percent between 2005 and 2012, with a 22 percent drop in crashes that resulted in serious injury. The city's data also indicate rear-end crashes decreased 7 percent at those intersections during that period.

But an independent study by the Chicago Tribune (subscription required) found that not only were the city's numbers about red light safety grossly exaggerated, it turns out that in many situations, red light cameras actually increased by 22% the number of serious injuries at intersections.

The records also show that the camera systems falsely accused thousands of people of running red lights. In 2009, the ACLU of Massachusetts put together a list of reasons why our state shouldn't consider implementing them. The data from Chicago illustrate that we were entirely right on all counts.

Red light cameras: dangerous and inaccurate, but highly profitable for the cities that use them.