That study, the mayor said in an interview last month, found that traffic deaths in Chicago had plummeted 60 percent near red-light cameras, cousins of the speed-detecting devices.
"If the report is wrong, you should go analyze that report."
As Emanuel prepares to introduce his speed-camera ordinance to the City Council on Wednesday, the Tribune has, indeed, analyzed that report. The findings raise further questions about how the Emanuel administration has brandished statistics to justify the push.
The mayor's report amounted to little more than a claim that traffic deaths declined significantly in areas where red-light cameras were installed over a three-year period. But the administration refused to provide any of the underlying research to verify their numbers, claiming it was confidential.
When the administration's numbers expert finally sat down with the Tribune after weeks of requests, he acknowledged the claimed reduction in fatalities was based only on an informal analysis of traffic statistics.
"Study is a bit of a term of art," Scott Kubly, managing deputy commissioner in the Chicago Department of Transportation, said earlier this month.
"We had many meetings to discuss the best and most fair way to gauge the effectiveness," Kubly said, including a "judgment call" to count fatalities as far away as a quarter-mile from red-light cameras. He declined to say who was involved in the meetings. Asked who he meant by "we," he said he meant "the royal we."
Denied the city's research, the Tribune performed its own analysis using city traffic data provided to the federal government and came to a very different and less dramatic conclusion.
Instead of the 60 percent reduction the mayor touted, the Tribune's analysis of accidents for the same locations revealed a nearly 26 percent reduction — one that mirrored a broader accident trend in the city and across the nation. The difference? The city said fatalities dropped from 53 to 21 in the targeted zones, but the federal statistics showed the before-and-after numbers were 47 and 35.
Presented with that conclusion, the Emanuel administration this week reversed course and said its initial statistical summary was error-ridden and shouldn't have been provided in the first place.
The mayor "inadvertently handed out a working document showing a set of incorrect numbers," Kubly said Monday. "I think it was an honest mistake."
The confusion fits into a pattern of inaccurate claims that Emanuel and surrogates have relied on to sell the mayor's plan to make Chicago the nation's capital of speed cameras. At the mayor's urging, Springfield lawmakers hustled approval for city cameras with little deliberation last fall.
Police Superintendent Garry McCarthy, echoing "talking points" prepared for mayoral surrogates, declared to state lawmakers that the rate of pedestrian fatalities in the city was far higher than in New York, where he had once worked.
In fact, the opposite is true, according to a study released by the city in August, which concluded that "relatively speaking, Chicago has a safe pedestrian environment given the volume of traffic."
Emanuel also sought to connect the tragic October death of a 6-year-old girl to the need for cameras, even though the youngster died while crossing a street at a time when cameras would not be allowed to operate under the mayor's program.
The mayor's effort also has support from the Traffic Safety Coalition, a pro-camera group run by close Emanuel political ally Greg Goldner and funded by Redflex Traffic Systems Inc., the Australian-owned red-light camera vendor for the city, the Tribune disclosed Tuesday.
Emanuel didn't answer questions about his ties to Goldner at a news conference Tuesday, asserting that his goal was saving children and that the process of selecting a speed-camera company would be "very open, transparent, very competitive."