I created a new red light camera map with revenue data obtained by Barnet Fagel from the Chicago Department of Revenue. The map below shows intersections that have generated $2,000,000 or more in revenue between 2007 to 2009. The complete data set lists the revenue for all intersections with red light cameras for each year (2007-2009). I have made it public, so please drop me a line if you find it useful.
Download the KML here
The Chicago Police Department (CPD) uses a formula to calculate whether your neighborhood should receive a camera. If your local corner gets a score of 100, then the CPD may place a camera on the corner. The formula is:
The formula relies on a 90 day period with a distance of about 200 meters from the camera location. So assuming you could get the data, here is a hypothetical analysis for 5000 W Madison:
100 Calls for Service = 100 points
20 Reported crimes = 40 points
25 Arrests = 50 points
Total = 190 points
The 190 points is above the threshold score of 100 and therefore 5000 W Madison could be a candidate for a CPD surveillance camera.
Unfortunately, the CPD doesn’t make it easy to calculate these scores. Only reported crimes is publicly available at gis.chicagopolice.org. Even then, the CPD restricts you to viewing 14 days of data at a particular location, even though they provide 90 days worth of data. The other two sources of data, calls for service and arrests, are not provided to the public by the CPD web page. Don’t get me started on the lack of crime data, it’s really an injustice!
A previous post focused on the extent of Automated License Plate Recognition (ALPR) in Chicago. It noted there were at least 75 locations (both fixed and mobile) operated by the police or OEMC that use ALPR. The post explores the effectiveness of the ALPR technology. For three different sources, here are some statistics on their effectiveness:
In the first ten months of the cameras (starting from January 2006), they had recovered 310 vehicles for the first 2.3 million plates scanned – see Sun-Times from Nov. 2006. By May 2007, there were 725 vehicles recovered and 6.5 million plates scanned. By spring 2009, there were over 13 million plates scanned and 1000 vehicles recovered. (The data also includes arrests). Here is a graph of the recovered vehicles over time:
I was a bit surprised when I saw these results (based on three data points). I would have expected a high rate of recovered cars initially and then a gradual taper to a plateau. First, I don’t have the most reliable data sources. Second, I don’t know much about the circumstances of how these cameras were deployed (how the cameras come online, how they were deployed, where they were use).
The average is one recovered car per day (using over 75 cameras). There are also 325,000 license plates scanned every month on average. If every camera is working equally, this works out to 144 license plates scanned per day with each of the 75 cameras. This is a very low number, because some of these cameras are capable of scanning 3,600 license plates per hour! I have no idea why this discrepancy exists.
I can’t fully explain this data, but I thought it would be useful to publish it. Please let me know if you have any explanations.
Automated License Plate Recognition (ALPR) is used throughout Chicago. It’s installed in over 40 vehicles. There are also 36 fixed locations. In 17 of those, license plate recognition occurs through real-time video. This is a major development. Using video from a pod camera, it is possible to automatically scan and process a license plate. Here is a summary from an article at officer.com:
Chicago-based EyeNet Enforcement Systems offers technology that can read license plates from video captured by the POD cameras. The camera and license plate reader system is approximately $10,000, and can be used with an existing camera. Some PODs are programmed to point in the direction provided by gunshot sensors and link with EyeNet’s license plate reader system.
Tom Tarach, CEO of EyeNet, says there were challenges with the implementation. “This had never been done before, but the Chicago Police Department was determined to make it work,” Tarach says. “With a few tweaks and adjustments we found we had a working system that could scan license plates from a video stream.” Tarach adds the Chicago police now have two EyeNet readers which can easily process real-time video streams from any of the city’s wireless POD cameras.
ALPR is also installed on the street sweepers. The system photographs license plates of illegally parked vehicles that block the path of the street sweeper, and a violation notice gets sent to the vehicle’s owner. The entire operation is fully automatic, requiring no training or action from the operator. I am not sure how extensive the street sweeper program is at this time.
The city of Chicago has tested gunshot detection technology for the last few years, previous posts on this can be found here and here. The CPD tested systems from ShotSpotter, PSI (their SECURES technology was acquired by ShotSpotter in April 2009), and Safety Dynamics. According to an article in the Sun-Times in Oct 2009, the city conducted three separate tests of gunshot sensors between 2003 and 2007 in the West Side’s Harrison Police District. Only on one occasion did the detection system send a warning prior to a person calling 911 to report the shooting. As a result, the city felt the gunshot detection systems were too expensive at a cost of $200,000 a square mile.
This mixed success concurs with a similar study on the effectiveness of SECURES gunshot detection system (not ShotSpotter) released in 2008 (based on data from 2005-6).
Despite the lackluster results, the city is going forward with installing the technology in the Loop. It will cover all two square miles. The technology will allow for real time updates on shooters, while distributing this information remotely. The cost is expected to be around $400,000.
[From CTA adds cameras to 24 Green Line stations :: CHICAGO SUN-TIMES :: Transportation]
The CTA is busy adding cameras as mentioned a few months ago. The CTA has now installed 1,657 cameras, with 73 rail stations covered. Part of this is a high definition camera at the all the entrances.
Cameras already are on CTA buses. Besides installing cameras on train platforms, CTA President Richard Rodriguez said each station will have a high-definition camera to capture the image of everyone who walks into the station. “We’ll be able to identify what time someone entered, and their facial features,” he said.
The cameras are seen as a deterrent to crime. Robberies went up 77 percent on CTA trains, platforms and buses between 2006 and 2008. Here are the funding numbers:
The CTA received $22.6 million in federal funding to expand its security and surveillance network. The Green Line project cost about $4 million, and the CTA plans to use another $9 million to add at least one high-definition camera to every rail station by this summer, as well as more cameras across the system — beginning with the Red and Brown lines. Remaining funds will be used to further improve the security network.
[From Chicago homicides drop for 2009 - chicagotribune.com]
Here are the stats:
2003 – 598
2004 – 448
2005 – 448
2006 – 467
2007 – 445
2008 – 510
2009 – 453
While cameras were mentioned last year as a strategy to drive down crime, they received no credit in the Tribune article. The CPD highlighted its city gang teams, use of informants, and analyzing crime data as the best explanations for the reduced crime.
[From Red-light cameras: State legislators having 2nd thoughts -- chicagotribune.com]
Now that legislators have seen how the cameras are used, they are not as supportive:
The chief author of the 2006 Illinois law that green-lighted suburban red-light cameras is now pushing a legislative revision that could effectively undo his original bill. The proposal, from Rep. Angelo “Skip” Saviano, R-Elmwood Park, would ban the use of cameras to ticket motorists for rolling right turns on red, a significant limitation that would strip away the financial incentive for municipalities to install the devices.
By some estimates, up to 90 percent of infractions flagged by cameras involve failures to make proper stops before turning right on a red light. While illegal, such maneuvers rarely lead to serious accidents.
. . .
But Saviano said the practical impact of the cameras has become distorted. “It went from a safety issue to a revenue issue,” he said. “The bottom line is people can’t afford to pay the gosh darn fines. They are grumbling.”
Saviano’s measure is one of several proposals to rein in the use of red-light cameras that have been filed by Illinois lawmakers in anticipation of the legislature’s 2010 session.
Chicago’s surveillance cameras were used to track Chicago School Board chief Michael Scott from a convalescent home to a lonely downtown spot along the Chicago River. By using the cameras, the police believe that Scott didn’t meet up with anybody else during that time.
This investigation highlighted the vast network of surveillance cameras in Chicago. Chicago has approximately 15,000 cameras at its disposal. Two thousand cameras are used for fighting crime by the CPD. The rest can be found at the CTA, airports, Park District, McCormick Place, public schools, and private cameras that have joined the city network.
Despite concerns about big brother, the current network is totally inadequate at monitoring every possible location. As I have previously pointed out, the current network of cameras covers only 5% of the city. (This does not include private cameras that are not networked to the city’s camera network.) Nevertheless, the city’s network is large and impressive.
To illustrate the camera network in Chicago, I am publishing a data set of 1,200 cameras used by the police. I believe this is useful to help educate people about the camera network in Chicago. I also hope that this data can find other innovative uses. I am very curious how this data will be viewed, used, and manipulated to other ends.
The data set can be viewed within either Google Earth or Google Maps through the KML file.
I will keep readers updated on how this information is used.
Update 1: I have also published the mapping data at GeoCommons, see the Chicago Surveillance Cameras layer. This should allow more people to use the data in additional formats, e.g., Shapefiles.
Update 2:
[From Chicago's red-light cameras don't always deter accidents -- chicagotribune.com]
I am hoping to review this data in a more detailed post later. But for now, here are some important snippets:
Cameras are said to reduce accidents, but collision records compiled by the Illinois Department of Transportation indicate that accidents increased at many city intersections the year after red-light cameras were installed. In fact slightly more intersections saw an increase than a decrease, the data show. The city tells a very different story. Crash statistics compiled by the city reflect broad success in reducing accidents with cameras, and the city could not explain why the numbers are so different.
The read from the state numbers is this: Although some Chicago intersections indeed appear to benefit from the presence of cameras, nearly 60 percent do not.
By year’s end red-light cameras will be installed at 189 Chicago intersections, the most of any big U.S. city. Sprawling Los Angeles, where the car is king, has 32; New York, 150.
This work casts doubt on the city’s claim that the cameras reduce accidents. (If the cameras don’t reduce accidents, then they aren’t providing the promised safety benefits.) Read the city’s claims here:
The City of Chicago reports crashes have been reduced by 20 percent in the two years since the camera technology was installed in early 2006 at 10 intersections. . . . Crashes decreased 30 percent, from 1,055 in 2004 to 736 last year, at intersections where red-light cameras were installed in 2004 and 2006, according to the Chicago Office of Emergency Management and Communications.
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