By on February 27, 2015

Chicago vs Recommended Yellow Light Time

Ever notice how the traffic lights in Chicago switch from yellow to red quicker than in other cities? That’s because the city changed the formula.

FiveThirtyEight reports the formula — yellow change time = 1 + (1.47 * Approach Speed) / (2 * Deceleration Rate) — was altered to increase the chances of a driver running a red, an act that would then be caught by the city’s red-light cameras, thus leading to a fine for the driver.

The formula used in Chicago is the one prescribed by the American Association of State Highway and Transportation Officials, which sets the deceleration rate at 11.2 feet/second over the standard formula’s 10 feet/second. The city also calculates yellow intervals by the posted speed limit, instead of the Federal Highway Association’s 85th percentile speed of real drivers, with the option to add 5 mph to the speed-limit yellow interval, as well.

The yellow interval — and its tie to the red-light cameras — have been a factor in Mayor Rahm Emanuel’s fight for another term in office, which has since entered the runoff phase after his campaign failed to gain an outright majority Tuesday. Emanuel’s support for the cameras runs in opposition of the city’s residents, 66 percent of whom believe the technology isn’t helping traffic safety in the least.

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44 Comments on “Chicago’s Yellow Light Intervals Generating More Fines...”

  • avatar

    I know where our red-light cameras are. My problem is the new ones which take a picture if you’re doing more than 30. My Jeep barely operates below 40.

    What’s worse is deblasio (no caps) set them up on main roads where 45 is reasonable.

    Go ahead and keep giving me $50 tickets.

    I’ve got FUN COUPONS….

  • avatar

    Makes me glad I joined the Free State Project and moved to New Hampshire where red light cameras, speed cameras, and automatic license plate readers are illegal. It’s amazing that people put up with being so blatently fleeced by politicians and their cronies.

    • 0 avatar
      jim brewer

      They don’t put up with it. It’s one of the reasons Rahm Emanuel was forced into a runoff.

    • 0 avatar

      Last fall we rejected them here in Ohio as well. To clarify – if a city is going to use them, then a police officer needs to be present as well. It effectively makes the cameras useless. Every now and again, Ohio gets it right…

    • 0 avatar

      New Hampshire also likes to station state troopers at toll booths to see what kind of violations they can find by peering into cars that don’t take the open tolling lanes.

      Before open tolling, I was going through the Hookset tolls at a time when the highway was nearly deserted. As I headed towards an open booth, the light changed from green to red. When it changed to red, I switched over to the next open booth, but apparently nicked the white line separating the lanes. As soon as I exited the toll, a State Trooper watching the booth ordered me to pull off to the side. I told him what happened and he went back to the booth to verify. I managed to get away without a ticket.

      It has to rank as one of the most absurd things I was ever pulled over for. When your “free state” decides it wants to collect revenue from motorists, they are experts at fleecing the public. Still, not as bad as some other states, but they’re hardly angels.

      • 0 avatar

        I designed the open road tolling gantries at Hookset.
        hope you like it!

      • 0 avatar
        jim brewer

        New Hampshire is smart: They rely on the corporate income tax for their money. They can’t jigger the system to take a disproportionate share, but they can have a high rate, and they do. They know that they are too small to be completely abandoned by the corporations. As long as the corps have sales in the state they can tax.

        • 0 avatar

          “New Hampshire is smart: They rely on the corporate income tax for their money”

          Much as it pains me to admit it, corporate taxes really don’t do much good in terms of general welfare: they’re a cost of doing business that flows through to the end-consumer. They’re also largely irrelevant to larger companies that can play jurisdictional tricks to avoid paying them entirely whilst they place a burden on captive SMBs, which will either fold or relocate.

          It’s exacerbated by governments that play a race-to-the-bottom, tax-wise.

          Better options would be a small sales tax with basic-needs exemptions, alongside by progressive property, inheritance and personal income taxes.

          • 0 avatar

            “alongside by progressive property, inheritance and personal income taxes”

            I really, really, really, really hate property taxes.

            Well property taxes in Gloucester Virginia at least.

            I’ve since moved to Newport News and I’m waiting to see what they zing me for but in Gloucester the property tax on my five year old GT500 was nearly 900 bucks. The depreciation according to the county amounted to around 100 dollars over a five year period.

            This was particularly galling when a buddy of mine with an 04 Cobra was paying less than 100 dollars a year in property taxes in Newport News.

      • 0 avatar

        Ah, yes, but they “tolls” not taxes. Tolls, user fees and fines are perfectly acceptable, it simple, broad-based taxes that are The Socialist Evil.

        • 0 avatar

          tolls are a way of paying for something when you use it and only by the people who use it.
          Toll roads are the LEAST socialist form of paying for roads. It’s almost pure capitalism, except the toll roads aren’t allowed to turn a profit. If you don’t like it, don’t use the toll road. that’s freedom, baby. Bask it in (while sitting in traffic) Your local county probably pays for its roads from everyone’s property taxes that’s the MOST socialist form of payment.

          who invented toll roads in America? Benjamin Franklin. You can’t get more American than Ben. Don’t be a Ben hater. Ben rules. Pay your toll and be happy knowing that the forefathers of this country wanted you to do it. ;)

          • 0 avatar

            “tolls are a way of paying for something when you use it and only by the people who use it.”

            Tolls and fees tend to be administratively inefficient.

            Not quite as silly as city and county sales taxes, but still challenging.

          • 0 avatar

            Unfortunately, Ben didn’t know a lot of what we know now.

          • 0 avatar

            tolls are magnificently efficient when collected by tag reader. The old way of using toll collectors was not efficient, but that’s become less popular.

          • 0 avatar

            What’s become more popular is taking existing highways and turning them into toll roads as well as planning the network to make the choices to the toll road purposefully less attractive.

            My favorite is 290 out of Austin. They added a toll BEFORE they expanded the formerly free route to and from the state capital. You get to pay money and time and alternates are pretty much limited.


    • 0 avatar

      Free State Project = dead end for silly libertarian fantasies of small government.

      Besides, we don’t have any of that speed camera shit in VT either.

  • avatar

    This is nothing new. Been going on for ages.

    Don’t forget their use of the cameras on rolling right on red turns. Yes TECHNICALLY you must make a complete stop. But studies say these turns pose extremely low threats. But you’ll get sent your fine just the same.

    Don’t forget Chicago also now has speed cameras. Sold as “it’s for the kids of course”

    And as mentioned the speed limits are also not correct. Way way too slow on some main city streets. And guess where they put the speed cameras.

    Don’t forget the parking meter deal!

    Oh and you have to have a city sticker for your car on top of the Illinois registration.

    Oh and don’t forget the confusing Street parking signage, and the draconian enforcement. 3 inches past that no parking sign? Enjoy your $60+ ticket. Or if you’re really lucky you get to take a trip to the bowels of Wacker Drive and pick up your car from the tow impound. A good $300+.

    I love Chicago, or at least a lot of it. I loved living there, usually. But you could feel a change when that meter deal started back in what, 08. And each year you just get more and more nickel and dimed and it’s painful 1000 papercuts style. These driving issues, high sales tax, high booze taxes, rental car fees, restaurant tax, etc etc.

    And the worst is that the roads are in horrible shape. Even newly redone ones are filled with Potholes within 1-2 winters.
    So I’m pretty sure all these road fines are not going to roads. Probably to pay legal payouts for the police misconduct, other ridiculous legal fees, the absurd public employee pensions, and trying to make debt payments.

    What I loved about Chicago is its world city feel but you also got a mix of real neighborhoods, families, local hangouts as well. But I swear they are making it nearly impossible to live that life there any longer. I get the feeling it is transitioning to wealthy and poor, and lost middle ground. Guess that’s probably all over America lately.

    • 0 avatar
      jim brewer

      Leave it to Chicago to show the rest of us “how we do it downtown” My city has a police brutality problem; Chicago has a CIA style “black site” jail. What other city would even think of that?

    • 0 avatar

      I spent a few weeks on a business trip to Chicago a year or so ago. It’s probably the worst “big city” I’ve ever spent time in.

    • 0 avatar

      One reason that we end up with these cameras is because we have the whackos on the other side who actually make an effort to argue that running red lights is a safe activity. When there are unrepentant scofflaws on the roads, there will be others who understandably want to be protected from them.

      Running red lights is a bad idea. Rolling through a red isn’t “technically illegal,” it’s just illegal and for good reason.

      It doesn’t rate high in crash statistics because during the course of driving, the opportunity to violate this rule does not happen that often. (Most of our driving does not consist of turning right at red lights, and it is fortunate that those who obey the law usually obstruct the path of the idiots who would be inclined to violate it.)

      Cameras are problematic, but red light running is also a problem. People who can’t respect the right of way should not be driving.

      • 0 avatar
        an innocent man

        Wouldn’t decreasing the yellow interval actually increase the incidents of people running reds? Anecdotal, but it seems to me that people are more likely to push their luck when the yellow “seems” unusually quick. That extra second makes a difference, at least in perception.

        • 0 avatar

          For the purpose of reducing accidents at an intersection, any highway engineer (I’m a retired one) will tell you to increase the yellow interval, and delay the green for 3 seconds after the red.

          Red light cameras are NOT intended to reduce accidents, their purpose is revenue. If there isn’t enough revenue to pay for the cameras, the intervals are shortened to increase tickets, reducing safety.

          If they DO pay for themselves, but the intervals are shortened to increase extra revenue as Chicago is doing, well, those governments value your revenue potential more than your life.

      • 0 avatar

        Agreed, but pols who can’t see the inherent problem with tickets for profit created by the way these things work should not be leading.

  • avatar
    its me Dave

    Not a politically astute move by Emanuel. Roads/traffic control are a non-partisan issue and one of the few for which voters will cross party lines without a second thought. The Daley machine was taken down by poor snow removal.

  • avatar
    John R

    Wilmington, DE ia a party to this, too. I went to fight the ticket there were some 30 people fighting the same ticket for the same intersection.

    One of a number of reasons I moved out of there…but the damn cameras are starting to creep into my new neighborhood.

  • avatar

    Don’t know Chicago, but the short yellow is more dangerous, no matter how many violations it creates. Cams reward poor engineering, be it speed limits, or yellow intervals. Here in NY, in Nassau and Suffolk, the Red Light cams mostly bust right turns on red without a full stop.

    Self defense is easy and cheap. the Waze app has crowdsourced photo enforcement locations and in NY, at least, is almost 100% accurate. If you don’t want google literally tracking you, you can buy a “points of interest” download for your Garmin, and I’m sure others. My $90 Garmin reliably bong-bongs near photo locations and shows an icon. It has been proven to be pretty accurate in NY and DC.

    Only a moron runs reds, but making it so you “run” the light by setting yellow intervals for violations, not for safety, is just a scam.

    After considering all the pro camera arguments, just think….if this COST money, not a single cam would ever go up.

    Nassau and Suffolk backed off, in the face of massive public outcry, from speed cams-meanwhile, NYC wants endless camera enforcement, and as most drivers are not NYC residents on a typical work day, this might end up being the commuter tax NYC wants. While Vision Zero has good points, massive photo enforcement of the 25 mph limit is a long term goal. Only the fact that NYC does not have home rule and the state must approve the cameras has saved us from becoming a Brit style camera hell.

    • 0 avatar

      “Here in NY, in Nassau and Suffolk, the Red Light cams mostly bust right turns on red without a full stop.”

      More accurately: right turns on red without a full stop in precisely the right location.

      A huge percentage of red light camera tickets for tolls are people who *do* stop fully, but do so forward of where the law technically requires it. Of course, you can’t see oncoming traffic from the legally mandated stop location — so to satisfy both the camera and common sense, you have to stop twice.

  • avatar

    Let the bipartisan dreams of ending red light cameras bloom like a thousand Lott-Breaux handshakes!

    It could even be a legitimate use of the federal government’s constitutionally-enumerated powers to generate a uniform traffic code that eliminates these things or at least eliminates the ability to be so tricky with the timing as to cause rear-enders instead of side impacts.

  • avatar

    Traveling from the burbs of Chicago, I have to recalibrate my braking foot every time I visit the pothole-infested roads around scenic Midway Airport. Drive like a normal, sane individual and it’s remarkably easy to get caught. Brilliant!

  • avatar

    Putin blushes when he meets Rahm Emanuel

  • avatar

    If you run a red light, it’s your fault in the end. You did it. Pay up. There really isn’t anything wrong with that idea and most voters will, for a time, support the cameras because of that.

    If the average amount of violations at an intersection is obviously high, yet steps like lengthening the yellow are not taken, does the jurisdiction bare any fault? What if they intentionally shorten the red and violations go up?

    What if there is a red light camera involved?

    Yes, each driver did the deed, but if you can flip a switch and the violations go up by 20%, and you flip the frigging switch, are you not culpable for the resulting blood?

    Clearly, the red light camera companies and the governments involved have killed for profit. What I want to no is where are the prosecutions?

    • 0 avatar

      In this case, they’re shortening the yellow without shortening the dual-red duration; they’re just pulling the red earlier without shortening the red-to-green interval.

      That’s fairly reasonable.

      It’s still a cash grab, but it’s not a safety issue per se: someone who rushes a red is going to do so unless (and possibly despite) there’s a human traffic cop.

      • 0 avatar

        First, that’s unusual and I didn’t get that in the story. Will read again.

        Second, not sure it matters. That would depend on how the formulas are adjusted for dual red, and each particular light.

        Besides that, what’s the justification? In most cases it’s going to be we need the money.

      • 0 avatar

        Short yellows kill because people slam on their brakes when they should proceed through the intersection, causing more rear-end collisions.

  • avatar

    Here’s my ethical dilemma. If I get a ticket for running a red light by a fraction of a second(true story), and then mouth off about it to friends and family, am I not just playing into the leviathan’s safety scam?

    Also true, when a real life officer stopped me for running a red I protested that the light was yellow when I crossed(I had watched it the yellow passed my headliner). So I went to court(as I explained to the officer I would), forcing the town attorney to take my case before the judge, call the officer into court, and then negotiate with me outside the court room. Man that is fun, bargaining down a moving violation into some parking infraction plus a fine. All while the court staff are making a DVD copy of the cop’s camera video.

    You should have seen the smile on the judge’s face, as all present knew it meant they could now go to lunch.

  • avatar

    Almost every where there are traffic cameras , this short yellow light problem crops up because the cameras are provided under contract on a per ticker portion of fee sharing of the Dollars gained .

    Obviously this is a scam and posting it here and showing up at your Town Hall , writing letters etc. really does work to get it changed .

    Good on you for spreading the word .


  • avatar

    One advancement that is happening that I really like is the countdown timers on the pedestrian signals replacing mere flashing hands. Where I live (not Chicago) they really help drivers, from a long distance away, understand how close the green light is to turning yellow. Helps reduce almost to zero the “do I stay or do I go” episodes. Of course, that presumably reduces the revenue-generation probabilities of the enforcing jurisdiction, so I hope the municipalities where I live don’t see this article.

    • 0 avatar

      I don’t understand on how people continue to get red-light tickets even with most if not ALL the intersections in Chicago have that little gem on the side. If it’s less than 3 seconds I let off the gas and coast up to the light. (It’s called get your vision checked people!) I’m not in THAT big of a hurry to run down people, cause an accident, or get a ticket just because I don’t want to sit at a red light.

  • avatar

    It’s hard to claim “safety” if you’re also reducing the light times. Welcome to “policing for profit.” Near me, the city of Milbrae dishes out fines north of $650. For my part, I’m currently fighting a ticket for parking in a handicapped parking spot that did not have a sign! (Fortunately, its a mere $317.)

  • avatar

    Whoa… A story about crooked politics in the “New Orleans of the north.” Where did I put my shocked face?

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