CDOT originally stated it would install and maintain the cameras at intersections with the highest "angle crash" - or T-bone crash - rates in order to increase safety.
The IG's office also said CDOT was unable to prove it regularly re-evaluates and updates its camera placements around Chicago. The IG's office said since the program started in 2003, the city has relocated only ten cameras from five intersections out of a current 384 cameras at 190 locations.
"For one set of cameras, the City is spending nearly 56% of the purchase price on maintenance expenditures each year," the report said.
The IG report also said CDOT was unable to prove the accuracy of the information it uses to determine where to place red-light cameras.
"The City cannot effectively manage its programs unless it measures its programs," said Inspector General Joe Ferguson. "In addition to finding that the City cannot prove RLC installation locations are based on safety considerations, we discovered a striking lack of basic recordkeeping and analysis for this $70 million program."
The audit was designed to answer nine questions posed by six members of the Chicago City Council, the IG's office said.
The audit suggests CDOT should implement and follow "clear" criteria for choosing red-light camera placement and keep records on the decisions and basis for each location.
CDOT responded that it intends to review the installation and removal criteria and determine what, if any modifications should be made and work with the winning vendor for red-light cameras in the city to ensure the criteria are met.
The full audit, and CDOT's responses to the audit findings, can be found online at the IGO website.
- Cicero and I-55 (19,805, $1,980,500)
- Lake Shore Drive and Belmont (16,273, $1,627,300)
- Lafayette and 87th (15,226, $1,522,600)
- Van Buren and Western (15,090, $1,509,000)
- 95th and Stony Island (11,449, $1,144,900)
- Laramie and Madison (11,224, $1,122,400)
- Stony Island and 89th (9,644, $964,400)
- State and 79th (8,769, $876,900)
- Pulaski and Peterson (8,612, $861,200)
- Cermak and Clark (7,923, $792,300)