Dear Mr Fitzpatrick,
Though I was already dimly aware of the government's plans to "harmonise" (we all know which way...) rural speed limits, I am deeply concerned by the plans you are apparently championing (as reported in various papers today) to reduce the National Speed Limit on all rural routes to 50 mph. I am also surprised that you are considering a move that will make many people (myself and everyone I have talked about this to today) reject Labour at the ballot box in perpetuity.
I can understand that a simple analysis makes one think that this will make road transport safer and greener, but you and I know (if you're on top of your brief, as I'm sure you are) that this is simply not true.
1. Modern cars are far safer than they were when the 60 mph NSL was brought in. Go and find and drive your first car again; you'll see what I mean. Drum brakes, crossply tyres, no ABS, no ESP, no airbags, no passenger safety belts etc...
2. It is simply not true to say that across the board modern cars are more economical at 50 as opposed to 60mph. Modern diesels in particular are more economical at higher speeds.
3. Has anyone bothered working out the economic impact this will have in the middle of a recession? I run a service company with a predefined radius of operation. If this measure is introduced, there can be nothing for it but to shrink that radius. I will probably then let one of my ten staff go. I'm sure I'm not the only employer who will do this.
4. Bad speed limits get ignored. When a limit gets lowered below the speed where a significant proportion of drivers will break it at their natural pace, people start ignoring the limit. I could name a road in West Dorset which went from NSL to 30, then when the powers that be realised how daft this was it went up to 40. I assure you that people drive slower now than they did when it was a 30 limit. This is why the 85th percentile method of setting limits works so well.
5. As you are well aware, speed is far down the list of accident causation factors. Only 6% are directly caused by exceeding the speed limit; the frequently wheeled out 1/3 stat includes all accidents where speed was a contributory factor, and by definition they wouldn't be prevented by a drop in the limit. I refer you to the DfT accidents stats
here (about page 42 if I remember rightly). Far more are caused by various factors related to bad observation at junctions.
So if you really have a missionary zeal to save lives, and don't just want to spoil drivers' fun, I urge you to use a limited road safety budget in a way that will actually save lives. You can't legislate to make drivers look more carefully at junctions, but you can invest in making junctions and roads safer, with far more effect than waving a crude legislative stick at them. I commend a book called "Road Accidents: Prevent or Punish" by Prof JJ Leeming to you. It may be 40 years old, but it makes more sense than anything else I've read on the subject. I hasten to add that it has recently been reprinted.
Yours sincerely
Johnny