The Right Turn on Red and some Free Ideas

Time to continue my series on traffic signals with the red-hot topic, the right turn on red, and some ideas for improving things.

The Right Turn on Red

We all know right turn on red (RTOR) is extremely dangerous, leading to motorists mowing down workers carrying plate-glass and old ladies pushing baby buggies. Or is it? Well, it seems to lead to a lot of aggressive behavior from both motorists and pedestrians, which has been well documented here on and even noted in official studies, but actual crash data shows it’s very safe.

California, with its wide streets and auto-centric culture, has had RTOR since 1939. The first study was in 1956 by James C. Ray in San Francisco, Berkeley, and Richmond which found just 0.3% of intersection crashes involved a RTOR. Also of note: RTOR maneuvers involved 11% of the right turning crashes but 18% of the total right turns (And the same motorists that can’t make a RTOR would make a right turn on green during the next phase, which has the issue of motorists not yielding to pedestrians, along with much higher speeds).

Later studies have similar results. For vehicle vs. vehicle crashes, a National Highway Traffic Safety Administration (NHTSA)  1989-1992 study of Illinois, Indiana, Maryland, and Missouri (selected because crash reports from those states included data on whether a RTOR maneuver was being performed) found they amounted to 0.05%, of all injury crashes, and 0.06% of all fatal crashes.  A 1994-1996 study limited to San Francisco found they amounted to 0.45% of all intersection crashes.

Nor do things change much for car vs. pedestrian crashes. A 1994-1998 San Francisco study (to determine if RTOR should be banned citywide) by Jack L. Fleck and Bond M. Yee showed just 0.8% of all car vs pedestrian crashes involved a RTOR maneuver. To try to see if there may have been some problems with reporting, they picked 100 random car vs pedestrian crashes to analyze in detail. They found that of the 25 that occurred at signalized intersections, zero involved right turn on red and 12  involved right turn on green. Quebec, long the lone holdout against RTOR, finally allowed them in 2003 after reviewing the studies.

There are some conflicting data: one study of several states (by Paul Zador, Jack Moshman, and Leo Marcus) showed that when RTOR was enacted crashes at intersections increased 20.7% from what they would have been but there was no significant change in severe or incapacitating crashes.  A similar before/after study by Claude Dussault had similar results. One possible explanation for the discrepancy is a learning curve from both motorists and pedestrians, and that when the law was changed there were specific intersections that should have had restrictions that hadn’t been identified and so marked yet.

I acknowledge the possibility that a lot of very minor crashes between cars and pedestrian are not reported. This is not something I’ve personally observed (I’m rarely outside a car unless I’m on recreational trails which tend to have few signalized intersections and I try to avoid driving in pedestrian heavy areas if at all possible).  However there have been no studies on this, just anecdotes, and thus I can’t support or refute them since there’s no data on how common they are in objective terms. No one chimes in and says “I was not knocked over by a car today”. Maybe that’s a good area for a future study?

The MUTCD Speaks

Here are the MUTCD guidelines for NTOR, section 2B.54 03:

A No Turn on Red sign should be considered when an engineering study finds that one or more of the following conditions exists:

  1. Inadequate sight distance to vehicles approaching from the left (or right, if applicable);
  2. Geometrics or operational characteristics of the intersection that might result in unexpected conflicts;
  3. An exclusive pedestrian phase;
  4. An unacceptable number of pedestrian conflicts with right-turn-on-red maneuvers, especially involving children, older pedestrians, or persons with disabilities;
  5. More than three right-turn-on-red accidents reported in a 12-month period for the particular approach; or
  6. The skew angle of the intersecting roadways creates difficulty for drivers to see traffic approaching from their left.

For a long time there was a no RTOR at Lyndale Avenue and 66th Street, but this was removed because there wasn’t engineering justification.  Of course this specific example is soon going to be a roundabout…

Lyndale Avenue at 66th Street

“Unacceptable number of pedestrian conflicts” is kind of subjective, so if they really wanted to keep the ban it they might have been able to justify it here, and I agree this might be a good place for one.  And this is only a recommended practice (The MUTCD has three levels of guidelines: “May”= Optional, “Should”=Recommended, and “Shall”= Required). San Francisco, in fact, bans RTOR in some places just to prevent motorists from inching into the crosswalk. .

But take another kind of intersection: If you ban right turns from a shopping mall to a wide suburban style road, traffic on the main road has to screech to a halt every time a motorist wants to turn out of the mall, and there’s probably not a pedestrian there and hasn’t been for the past hour. When you count all the suburban intersections around, there are probably more places they should allow RTOR than shouldn’t.

MN 252 at 85th Ave N.

MN 252 at 85th Ave N, no reason to ban RTOR here. Pedestrians aren’t even allowed at street level because of the pedestrian bridge.

My Own Thoughts

1) As should be obvious by now, due to the improved LOS for motorists and the preponderance of studies indicating it is actually extremely safe, I fully support allowing RTOR where appropriate. 

2) I don’t like city-specific bans like NYC, or Montreal where you have to be aware of different rules of the road. This diverges from everything we’re trying to accomplish now with standardization, and I think NYC can afford signs at this point.

3) As for whether the problem of motorists making illegal turns where banned is an engineering problem, enforcement problem, or both, I don’t know. Lighted blankout signs grab your attention, but have typically been used only at specific times of day, or when there’s a train on adjacent tracks. We use lighted indications for everything but a NTOR prohibition, so while not excusing bad driving, it’s understandable why it’s sometimes hard to see.


First Free Idea: Flashing Yellow Arrows for Right Turns

Directly related to the problems with right turning traffic at intersections, I propose increased use and modification of four section arrow heads on the right to try to make intersections safer.

The states that allow a right turn on a red arrow would have to change, and the MUTCD would have to allow a flashing red arrow, but this is how I see it operating:

  • Green Arrow: Go, no conflicting vehicle or pedestrian phases
  • Flashing Yellow Arrow: Yield to pedestrians or vehicles
  • Red Arrow: Stop and do not turn / Flashing Red Arrow: Stop and turn if safe

A four section head with a red ball on top is already legal if the intent is to allow RTOR, but I would prefer that we narrow the meanings of red balls , just as we are for green balls.

Three section flashing yellow arrow heads are now permissible, but installing a standard 4-section head may be more problematic when physically mounted on the post for right turns. The lack of positional change from a flashing yellow to a steady yellow would be mitigated because the through signals would always change at the same time. It seems motorists have a problem with the “yield to pedestrians” on a green ball, just like they do for “yield to oncoming traffic”on a green ball.

Second Free Idea: Ditch the Pedestrian Change Interval

The idea for a pedestrian signal got started when streets got wider, traffic got faster, and things got more dangerous for pedestrians stranded in the intersection when the light changed. So the “Walk” light was added to tell pedestrians when it was safe to leave the curb.

Early pedestrian accomidations, first with the green lens designed to throw some light downward, then with the seperate "Walk" lens

Early pedestrian accommodations, first with the green lens designed to throw some light downward, then with the separate “Walk” lens

Since then, we’ve added the “Don’t Walk” and countdowns, but we’re still telling pedestrians that we’re the better judge than they are if they can make it across. And the long clearance interval, designed to accommodate the slowest of pedestrians, encourages jaywalking and disrespect for traffic control devices, and destroys the LOS for law-abiding pedestrians.

Now that we have countdowns, what about eliminating change interval entirely and let pedestrians use their own judgement as to whether they can make it across the intersection? An 80-year old has a different crossing speed than a bicycle on the sidewalk or a multi-use path, but they are treated all the same. The countdown would start at the beginning of the Walk Interval, then count down to the buffer. We could extend the buffer a bit if we wanted to (but making it too long would again encourage jaywalking and reduce LOS). An eight second buffer, rather than the standard three, would allow 10 seconds of the red hand before the light turns green for cross-traffic.  Even at a narrow intersection, you could probably triple the walk interval. If a visually impaired person pushed a button, it could say “20 seconds left, Penn Avenue is 45 feet wide”. Would this increase crashes? I don’t know.

Third Free Idea: Bring Back Red Light Cameras.

To put it bluntly, as much as I like cars and driving, I have no tolerance for motorists that deliberately break the law and in 20 years of driving I’ve never been cited. One of my most satisfying moments was driving home from Biwabik and another motorist was tailgating me when I was driving the speed limit. I pulled over to let him pass, he zoomed by, and 10 miles later I passed him again he was pulled over by a cop. Red light cameras would also address the problem of motorists illegally turning on red where it isn’t and should not be allowed.

What sunk the initial red light camera program was that the Minnesota cameras only photographed the license plate, and it was a crime (a petty misdemeanor). The courts ruled that you couldn’t charge the owner of a car with a crime unless you had photographic proof it was them driving. The city of Chicago, with its extensive program, treats red light camera tickets as an infraction, along the lines of a parking ticket, and doing so here would likely be OK with the courts as we don’t require proof it was the owner that parked at that expired meter.


In the future I may write about such topics as the evolution of LED pedestrian modules or, but this concludes the “series within a series” of traffic signal controllers and questions.


About Monte Castleman

Monte is a long time "roadgeek" who lives in Bloomington. He's interested in all aspects of roads and design, but particularly traffic signals, major bridges, and lighting. He works as an insurance adjuster, and likes to collect maps and traffic signals, travel, recreational bicycling, and visiting amusement parks.

46 thoughts on “The Right Turn on Red and some Free Ideas

    1. Mike SonnMike Sonn

      And I know what “free idea” means. Just wanted to “complain” that a yuppie coffee shop wasn’t part of the “free idea” section.

  1. Bill LindekeBill Lindeke

    This is a thought provoking piece Monte, full of data and research. Having dug through traffic studies myself for my dissertation research, thanks for doing that! (For a relatively unresearched take on the same topic, see my earlier post: interestingly we agree about one thing and disagree about another!)

    Anyway, i think NTOR is really useful in specific places that have high pedestrian and/or bike counts. I don’t want to see it everywhere, but rather focused in places where we want to shift the balance between cars and people on the street. (e.g. downtowns, campuses, commercial districts, etc.) Think of it like a triage or focusing of attention. The main advantage for me is something you mention, keeping people from encroaching into the intersection or crosswalks.

    Too often these arguments devolve into an all-or-nothing debate, which is a legacy of the standardization you mention. But we shouldn’t be using the same approach for suburban arteries and walkable downtown streets!

    Anyway, great article.

    PS yes please Red Light Cameras will easily pay for the added signalization costs that Mike is complaining about.

    1. Bill LindekeBill Lindeke

      PPS. In the case of Dana’s accident yesterday, I think the real problem there is how to make on-off-ramps safe in walkable cities. These are the most dangerous places in our whole urban street system. Are there examples from other cities around the country or world of how to make off-ramps safe for people on foot or bike?

      1. Matt SteeleMatt Steele

        I think tightening up the lanes on approach would help. It would force a much slower right turn geometrically. Instead of pork chop islands or wide radius curbs, we could build bumpouts. This would 1. Make bicyclists and pedestrians more visible in the parallel and perpendicular crosswalks, since they’re closer to the center of the field of view for the motorist and 2. Create more observation and reaction time by significantly slowing motorists making such turns.

        Here’s an excellent piece on visibility and sight distances from the NACTO Urban Street Design Guide:

          1. Wayne

            They need to remove the truck route designation from a lot of streets in the city and force delivery companies to make the switch to smaller box trucks. The semis that are just on their way to the highway need to be funneled into specific routes that can support them (both with road design and actual maintenance because they destroy the streets). We don’t need to design every last street intersection just in case a full size semi truck might need to use, we just need to ban semis from smaller roads where they don’t make sense (and busy pedestrian areas).

  2. UrbanDoofus

    Well done. I also don’t support blanket bans on RTOR. Some intersections need it in Minneapolis, but not all.

    Regarding red lights cameras, such a shame. I do see drivers blowing red lights here all the time. I’ve never lived anywhere that I saw it on a daily basis until moving here. It’s quite dangerous. Is there any hope of reviving it to comply with the court orders?

  3. Evan RobertsEvan

    This is a great article, thanks for the detail and the ideas.

    Echoing others on the idea that the geometry of the turn is important in how safe the RTOR is. Where motorists have to take a 90° turn they come to a stop and it functions well. Where the angle is soft it becomes much more dangerous as at off ramps.

    I’m no engineer but in an urban environment where people are coming off freeways (as in the story by Dana) the geometry of the turn at the end of the ramp should be tight so drivers recognize they’ve transitioned from a freeway to an urban area.

    1. Wayne

      The corner radius needs to be tightened in general in urban areas. Even on corners with heavy pedestrian traffic you see big sloping corners that allow people to whip around corners without slowing down. My favorite is the corner of University and E Hennepin where the mail semis whip around the corner going 30+ mph on a pretty regular basis while people are jumping back on the sidewalk to avoid being turned into a fine paste. But that whole neighborhood is designated truck routes, so oh well! Nothing to be done, right?

      1. UrbanDoofus

        Wrong, There is something to be done.

        Please write to your local CM staff and ask them what they’re going to be about it, and how the current plan fits into the local small area plan. Me thinks over time that arrangement won’t work. That sounds like it is in Frey ward, so there you go: is very responsive and will even link you with county staff, as required.

        That intersection in particularly might work well for no turn on red because of the pedestrians, and the visibility of traffic coming from left.

  4. Walker AngellWalker Angell

    Great article Monte.

    Something I think our traffic engineers miss with looking at these purely statistically is subjective safety — how safe do people feel. Regardless of how safe statistics might say that something is, if people don’t feel safe walking or bicycling they’ll not do it. This is perhaps akin to being the target of a good knife artist. Statistically you are more likely to be killed riding in a car but who will choose being the target of a knife artist over taking their car to the corner store?

    Crossing many streets in the Twin Cities feels kind of like waiting for the next knife to be thrown. Our intersections need to be made actually safe and subjectively safe.

    Related to this is the extent to which drivers making RTOR without stopping cause pedestrians and bicycle riders who have right-of-way to have to stop and yield. For bicycle riders in particular this loss of momentum is quite a PITA.

    1. Monte Castleman Post author

      That’s pretty much why myself and a number of other people will not use marked bicycle lanes or lanes that are “protected” by thin plastic bollards (and of course using a vehicle lane is absolutely out of the question). Whether we’re safer on the sidewalk or not, and studies suggest we’re not, we feel safer with solid concrete between us and cars.

      I guess as a pedestrian I’ve never felt unsafe using a crosswalk. The area I live in has a lot of free right turns, so you wait for a gap in traffic, cross it, and then you know that none of the traffic on the main road is going to try to turn right. Obviously other people’s experiences are different.

      1. Wayne

        Anywhere with even a reasonable amount of traffic means if you play that waiting game you’ll be standing there all day. Making someone wait a ridiculously long time because they’re not in the preferred mode of transportation (a car, obv.) is asinine. If anything we should be decreasing wait times for pedestrians to encourage people making a choice that taxes our infrastructure less.

      2. Walker AngellWalker Angell

        I largely agree with you about riding in traffic lanes. I’ve done so for over 40 years but a gob of close calls, being hit a couple of times, and a lot of research has shown me just how dangerous it is.

        What studies suggest that riding on sidewalks isn’t safe? I’ve heard this numerous times but have never been able to find a study to support it.

  5. Walker AngellWalker Angell

    In addition to tighter radiuses, what about raised/tabled crossings? These not only help to slow cars but also better shed rain, snow, and slush making crossing a bit safer.

    1. Wayne

      I wish we could have nice things like these. But drivers whining about dinging the undercarriage of their car because they didn’t slow down and some hand-waiving about plowing will ensure we get few, if any, of these.

  6. Walker AngellWalker Angell

    Even if RTOR itself isn’t a significant cause of crashes, does it contribute to other crashes by encouraging higher speeds and less vigilance in general? We’ve become use to our roads being a racetrack?

    1. Monte Castleman Post author

      That’s a possibility, but it could work the other way too. Drivers tend to try to “make up” for what they perceive as their time being wasted by driving more aggressively. Put up a bunch of nuisance stop signs (those that try to control speed contrary to MUTCD recomendations), and they’ll stomp on the gas and driver faster between the signs than they would otherwise (plus eventually just start rolling through and then outright running them). Would NTOR where there is obviously no engineering justification have the same effect? I don’t know.

      1. Wayne

        Pardon me if I don’t trust those ‘engineering justifications’ very much when it comes to protecting pedestrians. Most drivers I see don’t even really do a rolling stop for the rights on red, they *maybe* slow down to 10-15 mph as they’re coming around the corner. They might stop (fully blocking the crosswalk) if there’s actually a car coming. They almost never actually stop back at the limit line and then proceed when safe. Right on red makes drivers think it’s ok to stop in the middle of the crosswalk by default so they can look for oncoming traffic. They never do the two-step stop and creep, which basically means if you’re about to cross the opposite way they’re looking you’re in the kill-zone.

      2. Monica Millsap RasmussenMonica Rasmussen

        “Would NTOR where there is obviously no engineering justification have the same effect”- ie drivers being more aggressive than they otherwise would be- absolutely. I have found myself in many dangerous situations where drivers waited to turn right on the green at a NTOR signal, watching only the traffic signal. As soon as the light is green for both the driver and me the pedestrian, the driver(s) almost always miss pedestrians waiting to cross and there may be several cars that turn quickly on the green before pedestrians can cross safely. My experience with RTOR intersections generally support the research done here. It would be interesting to see stats for driver/pedestrian crashes that happen on green at NTOR intersections. It would be interesting to see if there are any stats for any types of crashes that either happen or are reduced by signals and traffic calming contrary to MUTCD recommendations.

        1. Wayne

          You can add the early walk signal for pedestrians to NTOR intersections to give pedestrians a head start and be harder to miss.

  7. Danny Myers

    Such an informative article, really agree with the ideas you mentioned…Personally, I think despite many traffic signs, the main cause of accidents caused largely by the sense of obeying the traffic laws of the people.

  8. UrbanDoofus

    So how do we cut down on countless people who run red lights here everyday? Where is your solution?

    1. Wayne

      Or the people who block the box downtown each and every rush hour? Or the people who block the crosswalks as well because they had to try to make a turn onto a street with no room to accept their car and got stuck.

      A few thousand tickets might be a start to remedying this.

      1. Monte Castleman Post author

        Yes. People get killed and injured all the time due to right angle and car vs ped accidents caused by red light runners. Rear end collisions not so much.

      2. Rosa

        were you around for the “Don’t Block the Box” campaign? It might have been 10 years ago. It was pretty laughable.

        I really think tickets are the answer. Imagine how much cash the city would make around the new stadium.

    2. Wayne

      So they’re going too fast in the first place and still being bad drivers. I’d rather have them ding up their cars than T-bone in the intersection or kill a few dozen more pedestrians or cyclists.

      1. Bill LindekeBill Lindeke

        Red light cameras really piss off people who are used to speeding in cities, which is why they generate such animosity on the internet etc, and why news media LOVE covering them.

        My personal theory are the RLC’s are a really powerful tool in achieiving the overall goal, which is creating safe streets in walkable cities. Saying that they are a problem because they stop some people from speeding but not everyone only points to why we need to combine this really effective technology with other things such as reducing speed limits, narrowing lanes, etc., that will force drivers of cars to drive safely in walkable areas.

        I’m not saying use them everywhere, but as I mentioned above, to choose places and areas where there are a lot of people on foot or bicycle, and focus enforcement, engineering, and walkable streetcapes in those places. (e.g. downtowns, campuses, commercial districts, near schools and parks, etc)

        Here’s some actual data:

        Mixed results: “Even though the positive effects on angle crashes of RLC systems is partially offset by negative effects related to increases in rear end crashes, there is still a modest to moderate economic benefit of between $39,000 and $50,000 per treated site year, depending on consideration of only injury crashes or including PDO crashes, and whether the statistically non-significant shift to slightly more severe angle crashes remaining after treatment is, in fact, real.

        Even if modest, this economic benefit is important. In many instances today, the RLC systems pay for themselves through red-light-running fines generated. However, in many jurisdictions, this differs from most safety treatments where there are installation, maintenance, and other costs that must be weighed against the treatment benefits.

        The modest benefit per site is an average over all sites. As the analysis of factors showed, this benefit can be increased through careful selection of the sites to be treated (e.g., sites with a high ratio of right-angle to rear end crashes as compared to other potential treatment sites) and program design (e.g., high publicity, signing at both intersections and jurisdiction limits).”

        London, UK:

        On roads where we’ve introduced them, the number of people killed or seriously injured (KSI) fell by a dramatic 50%. That means our cameras help prevent 500 deaths or serious injuries each year.



  9. Morris Zapp

    So NYC should revoke its blanket ban, which prevents thousands of deaths and injuries a year, in favor of signs at practically every single intersection in the city?

    If you’ve never felt unsafe in a crosswalk you haven’t done much walking here. Right-on-green crashes are a leading cause of injury and death. Allowing right-on-red would only add to those numbers. Seniors account for a disproportionate number of pedestrian fatalities in NYC. Not everyone is spry enough to dodge turning vehicles.

    NYC doesn’t have the resources for the majority of improvements needed to reduce crashes on its deadliest streets. So no, the city can’t afford to spend millions to add sign clutter.

    1. Monte Castleman Post author

      There would not be thousands of deaths and injuries if New York conformed to the rest of the country and posted signs where RTOR is banned. Or even, according to the studies in my article. What if New York got a deal on white LED traffic lights because they were cheaper than red LEDs. Should we let them not conform to the entire rest of the country in that aspect too and make drivers change there expectations when they cross the magic line at city limits.

      1. Walker AngellWalker Angell

        Than again, we have the most dangerous road system of all developed countries (fatalities per capita and fatalities per mile traveled) and except for Greece our roads are more dangerous by a significant factor. The only one of those countries that allows RTOR is the one with the most dangerous road system — the U.S.

        1. Monte Castleman Post author

          Does that mean all the studies showing RTOR studies showing it’s safe are wrong, and that RTOR is why we have the most dangerous road system? Or is it possible that correlation does not mean causation.

          1. Walker AngellWalker Angell

            Correlation does not mean causation. However, correlation should give us pause for thought.

            We have over twice as many fatalities per billion km (7.6) as Denmark (3.4). We should look at and consider everything about how their roads are designed in order to make ours safer. A bicycle rider in the U.S. is about 9 times as likely to be killed per mile ridden as one in The Netherlands. We should carefully consider every aspect of how their roads and bikeways are designed to accomplish this.

            Statistics may not show the RTOR itself is directly dangerous but are there unintended consequences that we’re not capturing?

      2. Kevin

        I think you’re selling drivers way short if you think they can’t figure out the simple rule that if you’re in NYC, you can’t turn right on red. I used to drive there sometimes and it wasn’t that taxing a rule to keep in mind. Most intersections (in Manhattan, at least) you’d never have enough of a break in traffic to go right on red anyway. Why is “conforming to the entire rest of the country” in terms of traffic laws so important?

        1. Wayne

          To be fair, the sheer volume of accidents because of bad driving (be it distracted, reckless or other) kind of leads to the conclusion that you can’t trust people with a car to be safe with it. We need to use design and enforcement to curtail the bad behaviors people naturally slip into.

  10. Pingback: Right On Red isn’t dangerous ? « Berkshire Bicycle

  11. Spencer

    I’m curious, what are your thoughts about a blanket ban on RTOR except where permitted by signage? This flips the question on its head. Rather than asking, “are there enough pedestrians to warrant restricting RTOR?” we would have to ask, “is the risk of conflict low enough to make RTOR safe?”

    I recognize that 90% (don’t quote me on that) of traffic signals would probably warrant RTOR. However, many places where RTOR is banned by signage are already stressful and chaotic for drivers. Expecting them to notice a sign prohibiting RTOR may be asking too much. I’d rather have them look for the sign giving permission – at least if they miss that sign it doesn’t potentially endanger a pedestrian.

      1. Spencer

        I wonder if it would be possible to retrofit stoplights with flashing red arrows where RTOR is prohibited or something like that. Expensive, sure. But that way you don’t need to add sign clutter and everyone knows that if it’s a solid red you can’t turn.

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