# traffic light debacle **URL:** \ **Category:** Factual Questions\ **Created:** [June 15, 2010, 7:14pm UTC](https://boards.straightdope.com/t/traffic-light-debacle/543335 "2010-06-15T19:14:55Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![tropes](https://avatars.discourse-cdn.com/v4/letter/t/e5b9ba/32.png) [@tropes](https://boards.straightdope.com/u/tropes)\ **Post date:** [June 15, 2010, 7:14pm UTC](https://boards.straightdope.com/t/traffic-light-debacle/543335/1 "2010-06-15T19:14:55Z")
A power failure affected an large area of our city this morning. That meant traffic lights on some of the city’s busiest intersections were also out. Is there any law in North America which mandates that these intersections be treated as four-way stops? If not, there should be. ---
**Author:** ![needscoffee](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/needscoffee/32/1076_2.png) [@needscoffee](https://boards.straightdope.com/u/needscoffee)\ **Post date:** [June 15, 2010, 7:28pm UTC](https://boards.straightdope.com/t/traffic-light-debacle/543335/2 "2010-06-15T19:28:54Z")
In two states I’ve lived in, the law is to treat it as a 4-way stop. I suspect it’s that way in every state, but people either don’t remember it, don’t know it, or don’t care. ---
**Author:** ![Baracus](https://avatars.discourse-cdn.com/v4/letter/b/2bfe46/32.png) [@Baracus](https://boards.straightdope.com/u/Baracus)\ **Post date:** [June 15, 2010, 7:29pm UTC](https://boards.straightdope.com/t/traffic-light-debacle/543335/3 "2010-06-15T19:29:04Z")
Traffic laws aren’t usually applied continent wide, but many states have traffic laws that declare “dark” traffic signals should be treated as four-way stops. In my experience this works better for smaller intersections than for larger ones, where multiple through and turn lanes in every direction makes it rather difficult to determine whose turn it is. ---
**Author:** ![OldGuy](https://avatars.discourse-cdn.com/v4/letter/o/3bc359/32.png) [@OldGuy](https://boards.straightdope.com/u/OldGuy)\ **Post date:** [June 15, 2010, 7:30pm UTC](https://boards.straightdope.com/t/traffic-light-debacle/543335/4 "2010-06-15T19:30:50Z")
I’m sure every state has (nearly obsolete) laws on right-of-way at non-marked intersections. I know in Ohio it used to be the case (many years ago when I took my test) that when a traffic light was not operating the non-marked intersection rules applied. ---
**Author:** ![Pasta](https://avatars.discourse-cdn.com/v4/letter/p/ecccb3/32.png) [@Pasta](https://boards.straightdope.com/u/Pasta)\ **Post date:** [June 15, 2010, 7:37pm UTC](https://boards.straightdope.com/t/traffic-light-debacle/543335/5 "2010-06-15T19:37:11Z")
For a concrete example, here’s California’s [take on the situation](http://www.dmv.ca.gov/pubs/vctop/d11/vc21800.htm) (21800(d)(1) and (2)). ---
**Author:** ![Leaffan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leaffan/32/299_2.png) [@Leaffan](https://boards.straightdope.com/u/Leaffan)\ **Post date:** [June 15, 2010, 7:43pm UTC](https://boards.straightdope.com/t/traffic-light-debacle/543335/6 "2010-06-15T19:43:07Z")
Here’s what Ontario says about it: > [@](#): > > During an electrical power loss, traffic lights at intersections will not work. Yield the right-of-way to vehicles in the intersection and to vehicles entering the intersection from your right. Go cautiously and use the intersection the same way you would use an intersection with all-way stop signs. ---
**Author:** ![md2000](https://avatars.discourse-cdn.com/v4/letter/m/73ab20/32.png) [@md2000](https://boards.straightdope.com/u/md2000)\ **Post date:** [June 15, 2010, 8:04pm UTC](https://boards.straightdope.com/t/traffic-light-debacle/543335/7 "2010-06-15T20:04:23Z")
Yes, AFAIK, all Canada has the same rules (traffic is provincial jurisdiction). I recall a few weeks ago during a radio traffic report the announcers saying in harmony "Lights are out at X and Y street. Everybody repeat after me ‘Four-way stop!’ " No matter how often they say it, some people don’t get it. However, some intersections fail to flashing red one way, flashing yellow the other way. They also do this after midnight at less busy corssroads until 6AM. Flashing red - treat as stop sign, flashing yellow - don’t stop but watch for crossing traffic. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [June 15, 2010, 8:16pm UTC](https://boards.straightdope.com/t/traffic-light-debacle/543335/8 "2010-06-15T20:16:22Z")
Of course, many people don’t know how to deal with a four-way-stop marked by four stop signs, either. > [@](#): > > However, some intersections fail to flashing red one way, flashing yellow the other way. They also do this after midnight at less busy corssroads until 6AM. Flashing red - treat as stop sign, flashing yellow - don’t stop but watch for crossing traffic. I don’t think I’d call that a failure mode. When a traffic light does that, it’s doing what it’s supposed to do (generally because of very light traffic, such as late at night). And it certainly can’t do that if there’s no power (the most common cause of a traffic light failure). ---
**Author:** ![WhyNot](https://avatars.discourse-cdn.com/v4/letter/w/c77e96/32.png) [@WhyNot](https://boards.straightdope.com/u/WhyNot)\ **Post date:** [June 15, 2010, 8:25pm UTC](https://boards.straightdope.com/t/traffic-light-debacle/543335/9 "2010-06-15T20:25:13Z")
> [@tropes](#): > > Is there any law in North America which mandates that these intersections be treated as four-way stops? If not, there should be. Wait, is there any place where it’s NOT? What do they do, then? ---
**Author:** ![Folly](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/folly/32/3219_2.png) [@Folly](https://boards.straightdope.com/u/Folly)\ **Post date:** [June 15, 2010, 9:35pm UTC](https://boards.straightdope.com/t/traffic-light-debacle/543335/10 "2010-06-15T21:35:44Z")
I have to admit, I get confused sometimes at 4-way stops. Specifically, there is an intersection near me that has two lanes going North/South, four lanes in all, and one lane going East/West, two lanes in all. No dedicated turn lanes, so people turn left from the leftmost lane. If everyone arrives at every lane at the same time, when am I allowed to turn left from the left lane? (I’m pointed North, say) ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [June 15, 2010, 9:48pm UTC](https://boards.straightdope.com/t/traffic-light-debacle/543335/11 "2010-06-15T21:48:37Z")
If everyone arrives at once, the most aggressive driver goes first. If you arrive at the same time as traffic across from you, and want to turn left, you yield to them. Then you go. Anyone who arrives after you yields to you (in an ideal world). ETA: Rule of thumb for most cases: when you arrive, note who’s already at the intersection. After they’ve all gone, it’s you turn. ---
**Author:** ![Arkcon](https://avatars.discourse-cdn.com/v4/letter/a/96bed5/32.png) [@Arkcon](https://boards.straightdope.com/u/Arkcon)\ **Post date:** [June 15, 2010, 10:16pm UTC](https://boards.straightdope.com/t/traffic-light-debacle/543335/12 "2010-06-15T22:16:29Z")
> [@ZenBeam](#): > > If everyone arrives at once, the most aggressive driver goes first. Sportscars also have automatic right of way. 😃 Truckers who approach with the look on their face like they’d want to kill everyone on a good day have something called “Right of weight” so they get to go first. 😃 Back in the '80’s the “baby on board” sing meant, “I’ve reproduced, so I’m better than you”, nowadays, this is communicated buy driving an SUV, while holding a cell phone, and wearing the widest, darkest, sunglasses to avoid the appearance of eye contact. :rolleyes: Again, they go first. Grannies and people who drive like them may yield the right of way, at least until the guy, still two car lengths back, leans on his horn. 😛 The rules rapidly become more complicated after that. ---
**Author:** ![Joey\_P](https://avatars.discourse-cdn.com/v4/letter/j/919ad9/32.png) [@Joey\_P](https://boards.straightdope.com/u/Joey_P)\ **Post date:** [June 15, 2010, 10:32pm UTC](https://boards.straightdope.com/t/traffic-light-debacle/543335/13 "2010-06-15T22:32:48Z")
> [@Chronos](#): > > Of course, many people don’t know how to deal with a four-way-stop marked by four stop signs, either. > > I don’t think I’d call that a failure mode. When a traffic light does that, it’s doing what it’s supposed to do (generally because of very light traffic, such as late at night). And it certainly can’t do that if there’s no power (the most common cause of a traffic light failure). That is the failure mode around here. That’s usually what happens if one of the lights get’s knocked down. I suppose the city might come down after the find out what happened, evaluate the situation and decide if they intersection can function normally sans the downed light, but I always assumed the computer did it automatically. As for “dark” lights. I was always taught to treat it as a four way stop and regardless of what cars around me are doing, I will always stop for the light. However, a lot of cars don’t. I think it’s a combination of just not noticing the intersection and/or assuming that if they are on a busy road and the cross road isn’t a main road they can just go through it. ---
**Author:** ![jackelope](https://avatars.discourse-cdn.com/v4/letter/j/a6a055/32.png) [@jackelope](https://boards.straightdope.com/u/jackelope)\ **Post date:** [June 15, 2010, 11:15pm UTC](https://boards.straightdope.com/t/traffic-light-debacle/543335/14 "2010-06-15T23:15:01Z")
Tennessee Code Annotated, Section 55-8-110 (c): “The driver of any vehicle approaching an intersection that is controlled by a traffic-control signal that is inoperative because of mechanical failure or accident shall come to a full and complete stop at the intersection, and may proceed with due caution when it is safe to do so…” This code section came widely into play back in 2003, when Memphis’s infrastructure was basically shattered by a derecho (known locally as [Hurricane Elvis](http://en.wikipedia.org/wiki/Memphis_Summer_Storm_of_2003)). Much of the city’s was without power for up to two weeks, including traffic lights. Surprisingly, pretty much everyone took it in stride and treated all such lights as four-way stops. ---
**Author:** ![Superhal](https://avatars.discourse-cdn.com/v4/letter/s/b4bc9f/32.png) [@Superhal](https://boards.straightdope.com/u/Superhal)\ **Post date:** [June 16, 2010, 12:30am UTC](https://boards.straightdope.com/t/traffic-light-debacle/543335/15 "2010-06-16T00:30:51Z")
My state says 4 way stops too. ---
**Author:** ![Folly](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/folly/32/3219_2.png) [@Folly](https://boards.straightdope.com/u/Folly)\ **Post date:** [June 16, 2010, 12:31am UTC](https://boards.straightdope.com/t/traffic-light-debacle/543335/16 "2010-06-16T00:31:26Z")
> [@ZenBeam](#): > > If you arrive at the same time as traffic across from you, and want to turn left, you yield to them. Ja, but after they go, who goes next, me or the guy to my right going straight? Hypothetically, everyone arrived at the same time. ---
**Author:** ![Kent\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kent_clark/32/105_2.png) [@Kent\_Clark](https://boards.straightdope.com/u/Kent_Clark)\ **Post date:** [June 16, 2010, 12:48am UTC](https://boards.straightdope.com/t/traffic-light-debacle/543335/17 "2010-06-16T00:48:49Z")
> [@Folly](#): > > Ja, but after they go, who goes next, me or the guy to my right going straight? Hypothetically, everyone arrived at the same time. Yield to the vehicle on your right. ---
**Author:** ![Folly](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/folly/32/3219_2.png) [@Folly](https://boards.straightdope.com/u/Folly)\ **Post date:** [June 16, 2010, 1:25am UTC](https://boards.straightdope.com/t/traffic-light-debacle/543335/18 "2010-06-16T01:25:49Z")
> [@kunilou](#): > > Yield to the vehicle on your right. Ok. So I’ve yielded to the guy going straight. Then I yield to the guy on my right. In the meantime someone else has replaced the guy going straight. From their point of view, they just yielded to the guy on _their_ right and it’s time for them to go. Is it their responsibility to notice that I’ve been waiting a cycle and let me turn without t-boning me? I guess I’m confused if their is an ‘official’ time that the turners get to go, otherwise, it’s just people that are going straight taking turns assuming constant traffic in all directions. ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [June 16, 2010, 1:57am UTC](https://boards.straightdope.com/t/traffic-light-debacle/543335/19 "2010-06-16T01:57:19Z")
> [@Folly](#): > > Ok. So I’ve yielded to the guy going straight. Then I yield to the guy on my right. In the meantime someone else has replaced the guy going straight. From their point of view, they just yielded to the guy on _their_ right and it’s time for them to go. > Is it their responsibility to notice that I’ve been waiting a cycle and let me turn without t-boning me? > > I guess I’m confused if their is an ‘official’ time that the turners get to go, otherwise, it’s just people that are going straight taking turns assuming constant traffic in all directions. This new person needs to yield to all the cars already waiting when he arrives. That includes yielding to you even if you’re turning left in front of him. You yield to all the cars already present and waiting to go when you arrive. _In the case of ties_, you yield to the car on your right if you and he arrive at the same time. Similarly, _in the case of ties_ you yield to the car going straight across your path when you’re turning left. ETA: and of course, if you’re both going straight, you don’t intersect each other’s path, so you can both go at once. ---
**Author:** ![DesertDog](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/desertdog/32/11503_2.png) [@DesertDog](https://boards.straightdope.com/u/DesertDog)\ **Post date:** [June 16, 2010, 3:12am UTC](https://boards.straightdope.com/t/traffic-light-debacle/543335/20 "2010-06-16T03:12:20Z")
Just this morning, about 5am, I went through an intersection that had gone defective. I was on the main road and the lights for the intersection were blinking red. When I stopped and glanced at the lights for the side street, they were blinking red _and_ green. Being early, there was no traffic on the side street but if there had been, I would have made darn sure it was stopping before I would have ventured into the intersection. [Next page](https://boards.straightdope.com/t/traffic-light-debacle/543335.md?page=2)