Speed cameras: Are we interested in evidence?

If only other taxes were as easy to avoid.

The good thing about the speed limit tax (if you want to call it that) is that it's legal to evade (unlike a lot of other tax evasion).

Speed cameras are justified on the basis of road safety*. Which means we are being deceived.

* With the odd exception of reduced emissions.

Speed limits can exist for many reasons, they don't & never can define what a safe speed is.
The camera is just one method of enforcing said limit. The enforcement of limits is not restricted to reasons of safety.
There is no requirement to show any danger present for the offence of exceeding the limit to be complete.
It is a simple regulatory offence.

The problem with short slogans is they usually lose meaning as they lose length. Inappropriate speed kills is far more truthful. However the accurate statement, "Speed is one of many risk factors involved with vehicular conveyance, and increased speed increases both the probability and severity of a collision, all else being equal" doesn't quite have the same ring to it.

We don't seem to get as annoyed by "don't drink and drive", we understand it just fine. No-one outside of String Back Gloves Anon/Cupholders Haram/BRAKE is saying "never ever have a sip of a non alcoholic beverage whilst driving, even when safe to do so".

Indeed, no clue required, both the thread title and the op are quite clear. Yes the implementation of road traffic measures including speed cameras should be evidence based but (based on those studies so far) no government or local authority would spend huge amounts of money on further studies likely to undermine their aims - or that could be interpreted as such.

The evidence of my own eyes suggests that fixed and mobile cameras have limited impact on driving standards or road safety while also recognizing Vons point that these are not the sole reasons for such interventions.

That we penalise people for committing minor 'regulatory offences' while failing to deal with most of those who pose a real danger on our roads does rankle but the police can't be everywhere. I've no idea where we ought to go from here but with the exception of proven black spots or high risk zones the continuing proliferation of cameras isn't it.

Evidence/link please.....

That the 85th percentile is a fallacy. Evidence or link...

Read the question posed underneath the statement.
You can't get a true 85th percentile if a speed limit is in place, because the speed limit will affect people's choice of speeds.

I drive much faster on the autobahn than I do on UK motorways. Not because the autobahn is safer, but because I'd lose my licence in the UK for doing those speeds. I'd happily drive much faster in the UK but don't because of the penalty threats.The speed limit is affecting my choice of speed & when that holds true it skews any readings that attempt to establish a true 85th percentile. That's not only the case for me, but also for others.

30's affect my speed choice, as do every speed limit. Even when I'm not sticking to them rigidly. Because I'm also keeping in mind the thresholds for different disposal outcomes to avoid the steepest penalties if detected.

Many speed limits are political too including being seen to do the right thing to placate pressure groups.

Proposal to increase motorway limit to 80 mph was killed for that reason, even though it's the regular limit in Europe. Smacks of weak government.

Hmm, I beg to differ. Lots of things we can't simply "do" make perfect sense - like stealing, or fighting. A lot of speed limits make sense, however, a lot absolutely do not. Even allowing for all possible factors, some reduced limits are nonsensical.

Limits due to political point scoring, or limits overly enforced due to the ease of trapping just erode public trust in the system.

If the accepted norm was to "obey the limits" (because there are "rules") then there would be no reason for any sporty cars to exist - at all.