That sign telling you how fast you’re driving may be capturing license plates | Hacker News Reader

That sign telling you how fast you’re driving may be capturing license plates

qz.com

Enforcing speed when the intent is public safety rather than revenue generation requires more nuance than what the current system in the US has to offer.

Does it make sense to strictly enforce a 20 or 25 mph limit in areas with residential/pedestrian traffic? Certainly, especially given that pedestrians crossing a street are essentially at a 25 mph speed difference relative to perpendicular traffic. But if we apply this arithmetic to semi trailers traveling at 65 mph on the highway, a 25 mph difference would suggest a speed limit of 90 mph, even neglecting the safety difference in a vehicle-vehicle collision.

Where are most current speeding tickets issued? Is it in low-speed, residential areas where drivers know that an extra 5 mph won't save them any time at all (and would greatly increase the risk of injury in an accident)? Or is it in high-speed straights on the highway where an extra 15 mph can save you hours on long trips (where a speed limit effectively grandfathered from the malaise era still applies)?

Another consideration: if speed enforcement on highways was so critical to public safety, why are radar detectors and even laser jammers legal in many US jurisdictions? My perception is that physics-based policy decisions never get far in the US system. Ultimately, automated enforcement/better technology seems orthogonal to the policy problem. We should get the policy right first.

> Is it in low-speed, residential areas where drivers know that an extra 5 mph won't save them any time at all (and would greatly increase the risk of injury in an accident)?

Based on my personal experience in such areas, drivers very much do not know this. The number of people speeding down residential streets in my city just to get to a red light at the end of a block is astonishing.

For a comparison, the other week I drove 4000km across Europe and most of the speed cameras I came across were in areas where the speed actually makes a difference i.e. in towns and residential areas. Along a three lane motorway it doesn’t make much difference whether you go at 130kmh or 160kmh, if you aren’t paying attention and do something stupid it’s going to end badly either way. From seeing where speed was actually enforced, it seems that the authorities here believe that too.

In Germany, speed cameras are placed where accidents are likely to occur when the speed limit is exceeded.

Truck speed limits are lower than other vehicles exactly because of physics. Your suggestion that the speed difference is the thing that should be consistent across scenarios doesn't account for physics though. Kinetic energy goes with the square of speed, so the thing to look at is stopping distance from a given speed.

Most speeding in residential areas (both in frequency and in delta relative to the limit) is done by the people that live there. There was quite a bit of research done regarding this and one of the conclusions that stood out for me was that the familiarity with the territory was a big factor in this.

There is nothing in the article suggesting that the license plate readers in the signs would be used for speed enforcement. The big problem here is that the cameras are intended to be secret. Openly using license plate readers for actual speed enforcement raises much less serious issues as there are politically enforced limits on what the data can be used for.

> “We don’t know when somebody’s going to commit a crime, we don’t know when somebody’s going to run over somebody and take off,” said Joe Giacalone. “So that data should be there forever. We never know when we’re going to need it.”

That's a pretty tone-deaf response.

I don't see a problem with individuals keeping track of what vehicles or people coming into their neighborhoods or on their property. Or with remembering that for a long time.

If government needs to know, they can ask the public to check their records or get a court order if they suspect a specific route was taken during the commission of a crime.

Do I want authorities to be able to track dissidents wherever they go? No.

If you don't see a problem with individuals keeping track of who comes onto their property, what's the problem with the government keeping track of who comes onto their property (i.e. public space)?

Yet again, privacy advocates are trying introduce privacy into the public sphere, where it has no place. Privacy is to protect what you do in private, not what you do in public.

The difference is that individuals can't build a database that covers almost all public space and allows for large scale data mining, while governments can.

The other difference is that individuals don’t have a reputation for genocide, whereas governments certainly do.

Individuals who owned a lot of property definitely could. It's just a matter of degree, not a fundamental difference between individuals and government.

Also consider that said “individuals” may be corporations.

Meh.

On the one hand, I'm against tracking everyone, everywhere. On the other hand, I'm totally for ALPRs dispensing indiscriminate justice on people violating speed limits. I wish we could have auditable, trustworthy ALPR boxes that only report speed violations to be immediately turned into tickets, and don't store license plate numbers of people who follow the law.

Don't forget stolen, untaxed, and uninsured vehicles too

I really don't understand why we don't enforce speed limits more rigorously. We have the technology to do this at basically zero cost and speeding is one of the main causes of death on the road. Especially in residential areas where pedestrians and cyclists are around even moderate speeding dramatically increases the chances of deadly accidents. Doing 30mph instead of 20mph increases the chance of death for pedestrians from 5% to 45%. [1]

[1] http://www.humantransport.org/sidewalks/SpeedKills.htm

The real issue I have is that speed limits are selectively and arbitrarily enforced. This basically means that most people just end up breaking the law anyways and it allows law enforcement a convenient excuse to find a reason to fault someone.

> Doing 30mph instead of 20mph increases the chance of death for pedestrians from 5% to 45%.

What is this metric supposed to imply though? We obviously have roads with limits above 30mph already, so clearly decisions aren't made based on merely chance-of-death-assuming-a-collision being too high.

They’re based on chance of collision with a pedistrian and, in the UK at least, on that stretch of road’s history of such incidents.

So the figure shows that if there are more pedestrians likely to get in the way of your car then you should drive more slowly if you care about not killing those people.

The biggest problem with UK limits is when they reduce a limit for an unrepresentative peak in accidents.

When the figures regress to mean next year or two it's taken as proof the new limit was correct. So we slowly deviate from the 85th percentile rule, and get weird stretches of dual carriageway at 30 or 40 with a speed camera in the middle.

This metric is supposed to imply that "it's only ten over" is not a valid excuse to speed in residential areas. Unless you assume that 20mph limits are just there for fun and not because it's an area where it's likely that a pedestrian crosses the road unexpectedly or where you share the road with cyclists.

I guess what I was trying to get at was that you need to also consider the likelihood of collision in the first place. I'd assume that's also higher in residential areas -- not sure if it's just me, but I think that would sound like a far more compelling argument than just considering the chance of death assuming a collision.

Because speed limits are mostly arbitrary, your speedometer might be not as accurate as you expect and it's very easy to set a "speed trap"

Driving 50% over the limit is dangerous, fining people for going 2mph over is just "creating revenue".

Isn't there always some error margin. I know in my country it's something like +10kph +10%. Then the 130kph limit on the motorway becomes 154kph.

If you feel that your speedometer is not accurate you can always err on the side of safety and drive a little slower than allowed. Perhaps your brakes or your reaction time aren't as good as you think either. Besides, typical radar traps have an error of around 3km/h or 3%, whatever is larger, so it's unlikely that your speedometer is wrong enough to matter.

Often, lowering the limit is another option when dealing with road maintenance: can’t be bothered fixing one? Bump the limit down to 30km/h (car gearboxes aren’t even designed to drive at these speeds for long any more) and call it a day. If shit happens it’s someone else’s fault

> car gearboxes aren’t even designed to drive at these speeds for long any more

This makes no sense. Source?

Besides, 30 kmh limit is exceedingly common in European cities.

Here in Switzerland we have a lot of speed cameras and they are ruthless. 3km/h (1.9mph) over and you get a ticket in some areas. They are fully automated and ticket is automatically sent to the owner of the vehicle by mail. There are units in the city that bring in more than a 1 million a year each. The trend in deadly accidents is downwards but it's probably not only due to the massive fines.

A lot of the city has been reduce to 30km/h (18.5 mph) zones which drivers hate but makes it a lot safer for pedestrians.

[1] https://www.watson.ch/schweiz/strasse/861871246-in-welchen-s...

In many cantons there's an "error" allowance of 5 km/h when issuing a speed ticket. If the speed limit is 50, you won't get a ticket unless you were at 56 or more. This is done to account for car's speedometer inaccuracy.

One principal difference is Swiss traffic controls, at least in French-speaking parts, is that they prevent intersections of traffic flows. E.g. you can't turn left on a green that allows going straight unless cars in the opposite direction are held by the red. That is, if you are following the signs and lights, you will simply not have a chance to run into another car going in some other direction.

> I really don't understand why we don't enforce speed limits more rigorously.

Not sure how things are in the States but over here in Eastern Europe there are lots and lots of stupid speed limit signs, I call them "stupid" because if you were to follow them literally (instead of going with the traffic flow) then most probably you'd cause accidents for being an obstacle on the road.

There is a highway here that is engineered for 80 mph and the speed limit is 55. It is painful to drive on it.

Be careful what you wish for.

Red-light cameras in the US opened up all sorts of issues nobody thought about when they were just "totally for" ticketing people who ran red lights. We got issues like local governments tinkering with timing of traffic lights in order to increase the number of violations, because violations are lucrative and who wants to defend red-light runners? People who run red lights are bad people who do dangerous things, and they should be punished!

There are also the ongoing studies into whether red-light cameras actually increase collisions, by incentivizing people to stop unsafely.

And that's without getting into the due-process issues, or the way offenses start creeping into more expensive categories (see California cities which have been "upcoding" various other offenses, like rolling turns, into full-on red-light violations in order to collect larger fines).

Speed limits have a number of notorious issues; they tend to be set for political, rather than safety, reasons, and very few US jurisdictions actually follow the general best practice of setting limits based on 85th-percentile speeds. Some smaller towns infamously derive almost all of their municipal budget from running speed traps (i.e., a 55mph highway passes by, the town annexes a tiny strip of it and sets a far lower temporary limit, then tickets as many unsuspecting drivers as possible). What you're asking for is to industrialize all of those issues.

Links would be great here, but thank you for the eye-opening comment.

The town of Waldo, FL made the headlines a few years back: https://www.cbsnews.com/news/florida-town-infamous-for-speed...

You'd like to invoke Florida Man, but plenty of small jurisdictions rely on the income stream from fines. Ferguson, MO comes to mind. The police fleecing blacks and out-of-towners, it does wonders for the perception of the law.

Some anecdata for this: There is one intersection on my drive into work with a red light camera. There is also one on the way home.

Without fail, whenever I approach one of those intersections on a green light where the pedestrian signal has changed to a flashing hand, at least one car slows down.

I have seen people stop at a green light where the pedestrian signal is a solid hand (meaning the light will change to yellow soon).

Acting in an unexpected way is a recipe for an accident.

How common are the issues you mention? I hear a lot more complaints from drivers having to pay legitimate sounding speeding tickets than I do bogus tickets. In fact, I can't think of a single instance of anyone I know who got a speeding ticket that wasn't legitimate. Corruption in the process of enforcing the law is not inevitable too.

I also am not comfortable calling the "85th percentile" rule a best practice. Seems like a moving target that has more to do with perceived safety than actual safety. Here's someone else's take: https://www.strongtowns.org/journal/2018/1/25/speed-kills-so...

First of all, it's useful to distinguish two types of roads: those which are controlled-access exclusively for motorized vehicles, and those which are not.

Much of what you're trying to do is impose one-size-fits-all enforcement on both types. Controlled-access roads forbid pedestrians and bicycles, so arguments about protecting pedestrians and bicyclists on those roads fall flat. They should be using 85th-percentile metrics, in combination with the known design speed of the road, to set limits. But because controlled-access roads tend to have higher speeds, they're also the most tempting targets on which to run speed traps (i.e., if you can set a stretch of road to 25mph when the rest of it is 55mph, and park a hidden camera or cop right at the boundary, you can make a lot of money for your municipal budget, and precisely zero dollars of it will have been justified by increased "safety").

For the non-controlled-access roads, most of the real solutions the strongtowns/walkable/bikable/etc. movements want are going to come down to radically different infrastructure which have nothing whatsoever to do with speed limits. Speed limits are at best a non sequitur there.

I don't think you are responding to what I wrote. I never suggested a one-size-fits-all approach.

I don't think the 85th percentile rule is entirely bad, just not a "best practice", which sounds to me like "one-size-fits-all". The Strong Towns post I linked to said it makes sense for highways as I recall, which seems perfectly consistent with what you wrote.

Anyway, to reiterate, I am still interested in knowing how frequently speed cameras and the like are used poorly. The only uses of speed cameras that come to mind in my experience were not on "controlled-access" roads and seem justified to me. In fact, I rode my bike several times on one road with a speed camera that many drivers whined about back when I lived on the east coast. It was not uncommon for people to drive 15 mph or more over the speed limit there, despite the pedestrians. If I recall correctly the speed camera was added before a pedestrian crossing.

Edit: What I am recalling was actually multiple cameras on multiple roads. http://www.gazette.net/stories/12092010/laurnew185647_32536....

Auditability is important, especially given how wildly inaccurate* some of these 'speed detection' machines are. Most of the ones I have seen are pretty close, but some are clearly malfunctioning and would basically generate speeding tickets for 100% of the vehicles passing them until they are fixed.

*https://i.imgur.com/NF6eYb9.jpg

Your car likely gets its picture taken, and probably license plate automatically read, every time you drive through a toll booth, too. No one seems to be outraged over toll booths doing this, so why should any other public road sign (or private road sign that you, the driver, don't own) be any different?

Don't like being tracked by YOUR plate? Find other ways to achieve your transportation goals: ride a bike, take the bus, walk, use a taxi and pay cash, borrow a car, etc. Sure, you could be tracked by facial recognition but that's a lot harder to do currently than reading some very well defined characters from a highly visible license plate and it's much easier to legally change your appearance than to change your plate.

The ACLU says Any entity that uses license plate readers should be required to report.

https://www.aclu.org/issues/privacy-technology/location-trac...

That kind of sounds inclusive of toll booths.

Their 5 desired behaviors are admirable. The 2nd item, "The government must not store data about innocent people for any lengthy period." is hard to implement given existing police department budgets. The only way for you to know you can delete is to perform an investigation to verify you can delete. Doing that every few months on each plate isn't reasonable. You could speed up the process by having a national database but I imagine they would be even less happy about that.

I love the ACLU. I donate monthly. I fear a US without the ACLU far more than I fear a US with the ACLU. But every now and then I don't think they have completely thought out the opposing point of view or the realities of time and money.

I don't understand your logic. Why can't they just delete any information that isn't part of an active investigation? Because they don't want to take any heat from pro-authoritarians in the case that a later investigation could have used the evidence?

In the past police departments have been happy enough to just ignore rape kits for years and years. I guess people would flip their shit if unprocessed rape kits were destroyed, but that's specific evidence...

With advances in technology, the trend is that we are more and more able to catch speeding, red light passing, and other infractions. And it turns out a lot of people are eventually doing some.

I'm wondering what would be the consequences of a truly omniscient system, where each and every infraction would be immediately caught. We could maybe have mandatory black boxes in vehicles that transmit the infraction in real time.

It seems with a truly complete system, every driver would eventually run out of points on their license and wouldn't be allowed to drive anymore.

I started asking my family over ten years ago: What do you imagine life will be like when a super high resolution camera with terabytes of storage that can run on a solar cell costs $5? Because that’s where we’re headed.

I don't think following the rules of the road the vast majority of the time is that hard. Yes, you will make mistakes from time to time, but any reasonable system would recognize that. And sometimes following the law is less safe, but that's extremely rare in my experience. The problem is that many drivers, if not the majority of drivers, have no problem intentionally breaking the law as it suits them (e.g., speeding, unsafe passing, etc.).

I am a cyclist who rides with a helmet camera. It's amazing how much this seems to change some drivers' behavior. One moment they're rude and/or dangerous, the next they are keeping their distance and driving the speed limit. These drivers choose to drive dangerously because they think it saves time. (I'd argue the time savings are much smaller than they believe.) These people are the ones I think an automated system would catch, and I have no problem with that.

(As a cyclist, I follow the law to the letter, by the way. You will not catch me running reds. In fact, I have gone through the local police's stop sign enforcement efforts twice and passed.)

There are a lot of burglaries in France. The recognition of license plates combined with mobile phone location information would make it possible to identify burglars and even catch them in the act. All the data are available, it would be sufficient to collect them for analysis.

The "Vigilant" database mentioned is actually a product of a private company. There is essentially zero limitation or oversight on what they do with license plate data. From the point of view of the law, there is no expectation of privacy on a public street. One of their main customer bases are people who "recover" vehicles where the buyer is not keeping up with loan payments. They have thousands of private cameras in operation, making an ever expanding private dragnet available to anyone with the money to buy the data.

Looks like the US is getting ANPR https://en.m.wikipedia.org/wiki/Automatic_number_plate_recog...

Big US cities have had mobile license plate readers for a while:

https://chicago.cbslocal.com/2018/02/13/cpd-license-plate-re...

Just not coordinated at the national level yet. It would be pretty expensive given the size of the country, the number of police vehicles involved, and the current cost per vehicle.

There’s RFID antennas everywhere grabbing your toll tag number. Frankly this is a drop in the ocean of much more precise and voluminous data gathering on you. This one is the least of my worries.

It doesn't sometimes?

I hope it is, that's where I'd put the camera if I was in charge. Makes a lot of sense.

Only problem with that theory is that regular speed trap cameras are designed to be easily managed. Easily washed and easily replaced. So the end result is a big almost tower-like structure that in my country sometimes is empty depending on where they've deployed the actual camera, which sits inside this tower.

So placing a seemingly hidden camera inside a digital sign has some challenges. Like for example servicability and cleaning. Cars produce a lot of grit so having a large lens area that is easily cleaned actually helps.

They also work at night by using flash, which also requires some structure that might be visible.

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