Random ramblings

Monday December 05, 2005

"Report on the Use of Safety Cameras"

The Department of Justice recently released the working group on speed cameras' Report on the Use of Safety Cameras. The report examines "safety cameras" (nice bit of double-speak there) in the context of the proposed move to 'out-source' their operation from the Garda Síochána to the private sector (it's silly to have trained police operating cameras).

More paranoid motorists have long been cynical of some of the motivations behind speed limit enforcement. This report, in plain english, confirms the views of the cynics. Some initial highlights:

• Goals:

  Firstly, it sets out the goals of "safety cameras" in terms of reducing speed and increasing compliance of drivers to posted limits - a completely self-serving goal.

  There is scant mention of the real point of "safety" in the objectives, namely to reduce death and injury on the roads. It is accepted as fact, in a supporting section immediately following the objectives, that speed == increased risk, even though actual facts presented later in the report utterly contradict this naive view (the safest roads in the country are also the ones with the highest speeds, i.e. motorways and dual-carriageways). There is no examination at all of the actual effect of safety cameras on road safety, as you might think appropriate for a report that took 2 years to produce, just bald, naive assumption that they're a good thing.

  We could probably let this slide given general examination of road safety was not in the remit of this working group, but then the group shouldn't have tried to state objectives for speed cameras in these terms.

• Metrics:

  The metrics by which the success of "safety" cameras are to be judged are again self-serving, how many vehicles are checked, how many offences are detected, the rate of issue of fixed charge notices.

  Measuring the effect on accident rates, and qualifying success by this metric is not mentioned at all. The cynic of course would think this is because such a metric would interfere with the more important metric of issuing fixed charge notices (and the cynic's view is further confirmed, as we shall see).

• Funding:

  The report examines how private sector out-sourcing would be funded. It expects that initially the revenues will be "considerable", but will fall dramatically as more and more cameras come into operation and eventually motorists become generally compliant, though remaining high enough to cover the costs of the operator (and presumably their expected ROI). Initial revenue to the exchequer is projected at €70 million.

Here are the interesting, nay, nonsensical parts. The report recomends:

• Disproportionate enforcement on the safest roads.

  For motorways, which carry 3% of traffic volume but have %0.7 of fatal accidents (%0.5 of "speed related" accidents), and dual carriageways, carrying 4.4% of volume but %1.8 of fatal accidents (%1.0 "speed related"), the report recommends that each have about 2% of speed-camera-hours.

  So 4% of camera-hours are to be spent on the safest 7.4% of traffic volume, on roads accounting for just 1.5% of fatal "speed related" accidents. The cynic would point out that these roads are the "juiciest" targets because of their volumes.

• Revising speed limits on roads where people do not transgress.

  The absolute gem in the report though is the following direct quote on page 14, regarding the selection of camera sites with respect to the posted limit:

  1. The private operator will carry out a speed survey over a specific time period at the site. If the 85th percentile speed is above the actual speed limit (ie. 15% of drivers exceed the speed limit) the site will be considered for enforcement. If the 85th percentile speed is below the actual speed limit, the Gardaí­ will propose to the local authority that it consider reviewing the actual speed limit;

  Quote astounding; set the limits to ensure there will always be about 15% of people breaking the limit (the cynic would say to make sure the camera is paid for, but he's busy having convulsions). The only defence here is if this is done only for roads with high rate of accidents, which the appendix recommends, but it's difficult not to be cynical about this when revenue will become a consideration as compliance increases, as the report anticipates. Further, if the road has a very low accident rate, do you think they'll raise the limit?[1]

What a joke. You have to wonder if there's anyone with half a clue in the DoT. There must be clever and studied people there, yet no one appears capable of realising that formulating road safety policy mostly along the accepted "politically correct" dogma of "Speed baaad" has gotten us relatively nowhere (the other dogma, the more Irish problem of drink-driving, on the other hand has had an effect).

1. Setting speed limits according to the 85th percentile is common practice around the world. It has some serious problems. E.g. the 15% percentile is rather arbitrary. The bulk of the 15% of drivers above the limit are not per se the ones who cause accidents, particularly those in the 85th to 90th percentiles, who are likely quite competent. Further speed limits and accident rates do not strongly correlate. The main goal of 85th percentile limits are simply to allow majority of motorists to be in compliance (or maybe, to still leave a significant number out of compliance).

PS: FWEIW, I actually think speed limits are too high in many cases, particularly in suburban settings (50km/h here in Ireland). 20% of fatalities occur on local roads, according to this very report. It is in these settings where lower speeds could have the most dramatic effects on RTA fatality rates. Limits in suburban/local settings should be 30km/h IMHO, as on the continent.

Limits on safe roads like the motorway should, IMHO, be increased - significantly. To 160km/h at a minimum, preferably 200km/h. Remember, it's a limit, not a mandatory speed, the vast bulk of drivers will settle on what they consider to be a safe speed according to the 85th percentile rule. Only training and road awareness can affect safety after this. Penalising competent drivers for exceeding an arbitrarily low limit on quite safe roads is insane. Even worse, the absolutism of our system mean that you can face a greater penalty for exceeding a limit on a motorway than a proportionally greater infringement on a local road (the latter class being where excess speed is proportionally the more dangerous), e.g exceeding the 120km/h motorway limit by 65km/h (55%) versus exceeding the local road 50km/h limit by 30km/h (60%). The former can land you in court IIRC.

Enough ranting though.