To the Limit:
Not so fast

The UK has had speed limits longer than it has had motor cars. The idea persists that our roads traditionally had no speed limit, and that the imposition of the National Speed Limit meant eroding an historic freedom, but in fact restrictions on the velocity of road traffic have been a feature of British law for centuries. So how did we get the limits we've got?

Do the locomotion

The first true limit may have been the 1861 Locomotive Act, which regulated the use of steam locomotives and traction engines on the open road. It set a maximum speed of 10mph in open country and 5mph in towns, with fines of £10 for speeding (a term that has to be used loosely when the limit is 5mph). Convictions must have been rare because there was no instrument either on the engine or in the hands of the police that could have indicated how fast it was travelling.

The heady days of tearing around at a breakneck 10mph were short-lived. Just four years later, the Locomotive Act 1865 lowered speed limits to just 4 and 2mph. Presumably drivers would be convicted of speeding if a policeman couldn't overtake the engine at a gentle stroll.

The 1865 Act also introduced someone who, to this day, is oddly imprinted on the popular imagination: the red flag man. A 2mph limit meant that locomotives would often reach their destination faster by parking up and waiting for continental drift to take its course, but were still considered such an unimaginable danger that a man was obliged to walk 60ft (18m) ahead of them holding a red flag. The law is referred to, even now, as the "red flag act".

Red flag at the ready: steam traction engines like this were limited to 4mph in 1865. Click to enlarge
Red flag at the ready: steam traction engines like this were limited to 4mph in 1865. Click to enlarge

There are no records to indicate how many people were mown down by engines as they stared at the strange man who was so keen to show the whole street his flag. Evidently he was at risk of becoming a spectacle in his own right, because thirteen years later the rules were changed again so that the red flag was carried just 20ft (6m) in front of the engine.

The Highways and Locomotives (Amendment) Act 1878 was a further blow to the embattled Victorian driver, demanding that engines must stop completely on sight of a horse — something that must have virtually prevented them moving at all in towns.

Light relief

When the earliest motor cars were taken out on British roads, the limits of 4 and 2mph, and the requirements to bring a red flag and park up whenever a horse peered over a fence, were still in force.

Fortunately for would-be motorists, the Locomotives on Highways Act 1896 was passed just a year after the first petrol-driven cars were built, and recognised the self-propelled car as a new form of transport. It permitted "light locomotives" to travel at 14mph anywhere they liked without additional crew or red drapery.

In 1903 the car was properly recognised by the Motor Car Act, which introduced mandatory registration and a new national speed limit of 20mph. It quickly became an anachronism, as the new technology matured and cars were able to travel safely at speed, but it persisted for 27 years. Symbols of the new motor age, like the Great West Road and the first stages of London's North Circular, were subject to this 20mph limit when they first opened.

In fact, the blanket 20 limit was to become one of the least respected laws in British history, universally ignored and widely considered irrelevant. Speed traps set up by the police to catch speeding motorists were the reason the AA was instituted, with its patrols existing to position themselves ahead of the police and warn members to slow down.

No no, no no no no, there's no limit

Herbert Morrison MP, photographed in 1947. Click to enlarge
Herbert Morrison MP, photographed in 1947. Click to enlarge

It was the absurdity of the nationwide 20 limit that led the Labour Transport Minister Herbert Morrison to create the Road Traffic Act 1930, the legislation upon which modern motoring law is still based. His well-respected argument was that it's better to prosecute people who are driving dangerously than people who are on the wrong side of an arbitrary limit.

The Road Traffic Act abolished the speed limit completely, and in its place created the offence of "reckless driving". The motorist was free to travel as fast as they wished, wherever they wished, so long as they were not "reckless"*.

"Supposing we indicate that the speed limit should be increased to 30, 35 or even to 40mph, what are we saying? We are saying that in the ordinary run of driving a motor car it is reasonable to run at 30, 35 or 40mph...that is an exceedingly dangerous thing to say... The truth is that 40mph, 35mph, 30mph and even 20mph are dangerous speeds in many circumstances. 10mph or even 5mph, with some fool going round the corner on the wrong side, is a dangerous speed."

Herbert Morrison MP, 18 February 1930

Morrison was a brave man to remove the speed limit, but for two years his gamble paid off and the number of accidents on Britain's roads fell. Unfortunately, the trend then reversed, and deaths and injuries started to climb steeply. By early 1934, the issue of traffic regulation had returned to Parliament.

The proposed Road Traffic Act 1934 would change the law to create a 30mph limit in built-up areas, defined as places with a system of street lighting — a regulation still in force today. This was highly controversial, particularly because it came just four years after the first Road Traffic Act had set the motorist free from what were seen as malicious police speed traps.

Life begins at 30

In November 1933, the city of Oxford was given permission to create an experimental 30mph limit across the whole city, and Oxfordshire Police set up patrols in the suburbs. The experiment was discussed in Parliament as an example of what could be expected if the new 30 limit was brought into force. Oxford's MP argued that stopping speeding drivers on the way in meant that only slower, safer drivers made their way to the city centre. But not everyone was convinced. Within five months, 164 people had been prosecuted for speeding, but only two of them were also prosecuted for reckless driving.

"The obvious that in the opinion of the police 162 people broke the law...but that in the opinion of the police they were not driving to the danger of the public. That brings out a point which the Minister should remember — that if a man exceeds the speed limit he is not necessarily driving dangerously."

Sir W Brass MP, 10 April 1934

However, most MPs were in favour of the new limit, and the most contentious point was that it would not apply between midnight and 5am. That part of the bill was discarded after being roundly criticised; Lord Merrivale spoke for many when he said "I should like to know why people should be encouraged to drive at a dangerous speed in the dark".

New 30mph signs being manufactured at the Royal Label Factory, Stratford-on-Avon, in January 1935

Objections to the new limit were largely because the old 20mph limit had been so unsuccessful. Careful arguments were made to set the two limits apart.

"...the objection to the old speed limit was that not only was it in itself unreasonable, but that it became a dead letter and was impossible to enforce. I think this restricted thirty miles per hour speed limit is reasonable in itself, and we hope the vast majority of motorists, who are reasonable people, will take that view also, and will respect the law."

Earl of Plymouth, 17 July 1934

The absence of a general speed limit was one of the reasons that a specific urban was thought acceptable to motorists. 30 was judged to be a speed at which reasonable progress could be made but at which it was still possible to stop quickly when the unexpected happened. Its intention was to help drivers deal with the bad habits of other road users, and transport minister Oliver Stanley even hinted that it might only be needed as a temporary measure, to be removed when pedestrians were better behaved.

"When you get to the built-up area, which is all houses and all crossings, then you get to a place where the unexpected usually happens. It is there that you get the child who has been playing on the pavement suddenly running on to the middle of the road. It is there that the errand-boy comes round on his bicycle with both hands crossed in front of him. It is there that the pedestrian with an umbrella over her face suddenly walks on to the middle of the road. If you are going at 20 or 30mph, with your vehicle under control, there is a chance that you will be able to save those people from the consequences of their own mistake. But if you are going at 50 or 60mph they are dead. It is not a question of dangerous driving on the part of the motorist...

"The 20mph speed limit failed because it did not commend itself to reasonable people, but I do not believe that reasonable people will think it a great deprivation to be restricted to a speed of 30mph in these built-up areas while in the open country they are allowed to go at the speed which they consider to be safe."

Oliver Stanley MP, 10 April 1937

The new law was passed, restricting urban roads to 30, but there was still no limit on the open road, and Britain still had some of the world's most permissive speed limits. Elsewhere, the motorist was often restricted to very low speeds indeed. These are some examples of speed limits in other countries in 1934.

Austria In urban areas, between 25 and 35km/h (15-22mph)
Belgium In urban areas, between 20 and 35km/h (12-25mph)
Denmark Nationwide limit of 60km/h (37mph)
Norway Nationwide limit of 45km/h (28mph), except on "straight roads" where 60km/h (37mph) was allowed
Illinois, USA 15mph in built-up areas, 25mph anywhere else inside an incorporated city, 45mph in open countryside

A speed limit that applied in some places and not others called for new signs to distinguish restricted roads. On entering a restricted area, a new sign with a clear "30" made things obvious enough. But what could be used in the other direction, to indicate a derestricted road where no limit applied?

The answer was a sign that is still with us today, and might be one of the least intuitive and yet best understood road signs on British roads. The derestriction sign was a simple white disc with a black diagonal bar across it.

What a strange symbol: a National Speed Limit sign against a blue sky. Click to enlarge
What a strange symbol: a National Speed Limit sign against a blue sky. Click to enlarge

At face value it doesn't immediately suggest any particular meaning. But the key is in the definition of a 30mph road: one with a system of lighting. The derestriction sign was meant to show the end of an area of lighting, so it shows pure white, firmly crossed out.

Into the fog

Derestriction seemed, in 1934, to be an inalienable right of the motorist, one that Parliament was reluctant to take away. In 1965, that changed, quickly and very loudly, as stories of horrific and deadly pile-ups in the fog on Britain's brand-new motorways came one after another.

Tom Fraser, Minister of Transport, was faced with the prospect of another winter of tragic accidents and damaging headlines. His response has been discussed on before, in the shape of the "yellow peril" Motorwarn signals, and it included an experimental speed limit of 70mph on all derestricted roads.

21 December 1965 was the last day on which it was legal to drive at any speed you pleased on the open road in Great Britain; from the early hours of Wednesday 22 December all roads without a lower limit were subject to the new experimental limit of 70mph.

Opposition — from motoring groups, car manufacturers and others — was considerable, even with the fog panic that prevailed over any discussion of the motorways at that time. The Times carried an editorial warning of the risks of "the drowsy inattention which arises in the mind of the driver who, regulated by general speed limits, may fail to give his full mind to the ever-present hazards of driving at speed".

The M4 in the fog. The new 70mph limit was supposed to make motorways safe in poor visibility like this. Click to enlarge
The M4 in the fog. The new 70mph limit was supposed to make motorways safe in poor visibility like this. Click to enlarge

The complaints had little effect. Fraser's four-month experiment was extended further and further while its effect on accident rates was evaluated. An improvement was demonstrated, and that — perhaps combined with a reluctance to be the one who authorised motorists to drive as fast as they liked — meant that successive Ministers saw fit to keep it.

In the oil crisis of the 1970s it was lowered to a blanket 50mph nationwide in an effort to reduce fuel consumption, and was never restored to its previous state: instead we arrived at the present mix of 60 and 70mph.

We have now had a National Speed Limit for much longer than we ever had No Speed Limit, and the era of true "derestriction" lasted just 31 years. The experimental four-month limit is still, technically, a temporary measure, but it's now been with us for more than half a century.

Limits continue to be set and changed all the time — a business that requires a closer look.

* The Road Traffic Act 1930 did retain some limits — 30mph was the maximum speed for vehicles that carried more than seven passengers, and 20 was the limit for vehicles without pneumatic tyres.

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