Traffic Management

by Kenneth Todd

Highway agencies hold the highways in trust for the benefit of the people. The primary purpose is the interest of the public, which must be paramount to all other interests.1

The purpose of traffic control is to assure safe and expeditious travel at an economic cost to the road user and taxpayer and with the least inconvenience to everyone. In the words of London’s former Mayor, Ken Livingstone, his transport policy aims to manage “traffic to assist the movement of people, goods and services – safely, expeditiously, reliably and with minimum negative environmental impact”. Regrettably, Britain’s traffic management does not meet these goals.

Today’s traffic control system originated in the 1920s. It was put together by public officials who knew little about regulating the movement of the automobile, the new means of locomotion at the time. The records show that they adopted traffic laws on the basis of personal opinion without research into their safety and operational effectiveness.

Into traffic regulations crept inconsistencies and misconceptions that have killed innumerable people, cause massive traffic jams and involve the taxpayer in vast unnecessary expenditure. Traffic is being operated in an unsafe and inefficient manner, causing congestion, wasting time and fuel, damaging the economy and polluting the air, with severe negative impacts on public heath and the environment. Official reports in the USA have attributed 40 percent of the delay in urban areas to traffic signal inefficiencies.2   No such studies could be traced for Britain.

Traffic regulations should forbid acts that cause danger and obstruction. Current regulations not only forbid acts which cause no danger or obstruction; they encourage and command acts which do. The system runs counter to legal, engineering and safety principles, to the aims of the Traffic Management Act and the recommendations of the Road Safety Good Practice Guide.

History: Before there were any statutory traffic regulations, the relationship between all road users was governed by common law. No-one had a superior right; all had equal and mutual rights to be exercised so as not to interfere unreasonably with the rights of others. All were required not to cause unnecessary obstruction and use such care for their own safety and that of others as a reasonable person would under the circumstances. Equestrians, drivers of horse teams and motorists had to be on the look-out for pedestrians and have their vehicles under such control that they could avoid a collision. The increase in the number of automobiles and their higher speeds gave rise to the concept in the 1920s that there should be a rule to determine who should proceed first when two vehicles met at a junction.

In 1929, a commission chaired by Scotland Yard police commissioner, Sir Henry Maybury, held extensive hearings to find the most suitable priority rule at junctions.3 Stenton Cooke, chairman of the Automobile Association, proposed the use of the “off‑side rule”, which his organisation had advocated since 1921. The rule required every driver who arrived at a junction to give way to traffic from the right, regardless of the volume of traffic or the importance of the intersecting roads.

Instead, the Commission adopted the alternative proposed by Mervyn O’Gorman of the Royal Automobile Club with the support of the County representatives. They argued that the many fast drivers on important roads should not have to stop for the few coming from every small side road. All roads should be graduated in accordance with their degree of importance, and traffic on the less important road should give way to traffic on the more important. The rule should not absolve drivers on the more important road from the responsibility of exercising special caution at all junctions.

The Commission also adopted the concept of the roundabout, which William Phelps Eno, the American “father of traffic control”, had conceived at the turn of the century and proposed to Scotland Yard in 1924.

Moreover, the Commission adopted the use of traffic signals as a less costly alternative to police control at busy junctions. Members of the Commission visited Manchester and Wolverhampton, where they were greatly impressed when they saw traffic signals in operation. The cost of installation was about £100 to £150 per site, and the weekly upkeep 15s to 20s. By comparison, the weekly cost of a police constable, including wages, uniform, housing and pension, was £6 or £7. A set of lights might even relieve two constables for other duties, helping avoid large increases in the police force.

However, the Commission did not consider adopting both the major-minor road rule, for locations where minor-street traffic had no difficulty entering or crossing the major road; and the offside rule, where traffic was heavy enough to require the presence of a police constable or traffic signal. It was not until 1966 that the offside priority rule came into being, but then only for roundabouts.

No trials were conducted at the time to assess the safety and operational effectiveness of any of the proposed measures.

Nor did the Commission consider the use of a “first-come, first-served” alternative, which was common law and common practice before there were any priority rules. People about to enter a junction of two roads gave way to people who were there first, as they still do today at junctions with no control, or when traffic signals are out of action.

Accidents:  No sooner had traffic on major roads been granted priority when side-street drivers and pedestrians found they could not get across the large volumes of vehicles these roads were carrying. The major-road concept encourages drivers to travel fast without looking left or right, relying on minor-road drivers and pedestrians to keep out of the way. This was contrary to the original intention that those on the more important roads had responsibility to drive with special caution at all road junctions. It is also contrary to the Road Safety Good Practices Guide (4.12) which states that reduced vehicle speed is the most important urban safety factor, particularly for pedestrians and cyclists. The Guide (4.134) also states that the number of conflicts should be minimised. Road users should have to deal with only one conflict at a time. That’s why the pedestrian’s friend is the centre refuge, which lets him cross in two stages. The minor-street driver, instead, has to cope with two vehicle conflicts when crossing a major road, one from the right and one from the left, and – when turning right – with a third from oncoming vehicles. The more conflicts drivers face, the longer is the delay and the greater the hazard of distracted attention and entering an inadequate gap.

The root of the problem lies in the irreconcilable contradictions between statutory priority rules and common law. Under common law, all road users had an equal obligation to avoid danger and obstruction. By contrast, priority rules undermine the responsibility of the major-road drivers and place it on the drivers and pedestrians who want to cross. We need no scientific research to know that safety is jeopardised when two road-users are on a collision course and one of them thinks he can rely on the other to avoid the accident.
The dangers of crossing a busy major road has given rise to the public’s faith in the traffic signal as a safety device. Yet it has long been known that traffic signals cause accidents. In 1934, the Under Secretary of State for Home Affairs, Douglas Hacking, stated that statistics showed traffic signals to be responsible for an increase in accidents.4

Traffic signals compress an hour’s traffic into half an hour of green time and thereby halve all headways. Drivers go fast and keep close the vehicle in front for fear of missing the green light, with their eyes in the air rather than on the road. The combination of high speed, tailgating, diverted attention and sudden, often needless, stops provokes rear-end crashes. The Road Safety Good Practices Guide states that traffic signals cause accidents to pedestrians, particularly in congested conditions, and advises against their use where possible. An Australian study called signalised intersections the most dangerous sites on the road.5   

Needless delays:  The public is acutely aware of the needless delay at red lights, when we have to wait while no one is using the green. Requests to the Department for Transport, Transport for London and local authorities under the Freedom of Information Act have failed to establish a justification for needless delays.

Travel on the public road is a fundamental right. To restrict such right, the government must demonstrate a public interest. DfT officials claim without evidence that the needless delay contributes to safety. The DfT has not produced evidence that any alleged safety benefits of needless stops and delays outweigh the loss of time and fuel, the damage to business and health, the air pollution, the adverse effects on the cost of living and the climate, and the added risk of rear‑end collisions. They have not shown that motorists are competent to use their judgement when crossing unsignalised junctions but incompetent when crossing signalled ones. The law considers pedestrians competent to cross a road against red. There is no evidence to show they become incompetent when they are behind a wheel.

The traffic signal was originally intended as a replacement for the policeman on point duty. A policeman who stood in the street controlling traffic that existed only in his imagination would end up in a mental hospital.

Loss of capacity: Less obvious to the public than the needless delay is the loss of junction capacity and the congestion caused by priority rules and traffic signals.

A junction is a space of limited dimensions which people must use in a sequence that minimises mutual interference. We normally let people out of a confined space — a train, bus or plane — before we try to get in. A bus driver who insisted that passengers get on before the others get off would have to keep company with the mentally deficient policeman. But traffic control is based on the concept that drivers who have priority should enter a junction and obstruct those who are trying to leave. Whenever a driver on the left has priority over the one on the right, traffic gets blocked.

Rule 173 of the Highway Code shows a car trailing a camper. It has entered the junction and got stuck in the middle of the road. If the drivers on its left slowed down, it could move on without a traffic light. But the DfT claim it is illegal to put up a GIVE WAY sign to slow traffic on a major road. Rather than slow the vehicles on the car’s left, they use traffic lights to stop major and minor roads alternately, and forbid turning left when it is safe to do so. The underlying principle is to stop drivers to spare them the inconvenience of slowing down.

Or take the case of the green car, which is about to turn right. The Highway Code, Rule 180, tells it to give way to opposing traffic. In consequence, it is obstructed from leaving the junction, so that those who want to go straight on get blocked behind it. This practice — and the frequent remedy of installing right-turn lanes and multiphase signals — have not been shown to be safer, more efficient or more cost-effective than letting the right-turners complete the turn without giving way to oncoming traffic.

Note: apologies, illustrations have been lost in the upload.

 Zero-roundabout RRL 1968

Other Alternatives: In the light of the Road Safety Road Practice Guide’s recommendation that the use of traffic signals be avoided, we would expect everything to be done to employ safer, more effective and less costly alternatives. The mini-roundabout is such an alternative, but it is not the only one. A junction will work like a mini-roundabout without a centre island when everybody gives way to traffic on the right. That’s what the Automobile Association suggested 80 years ago.

Photo missing

This somewhat faint 1973 photo shows a bus route in Stoke-on-Trent where vehicles give way to traffic from a low-volume side street, thus avoiding the use of traffic signals.

Furthermore, as mentioned, before the adoption of priority rules, drivers about to enter a junction gave way – under custom and common law – to those who arrived first or were already in the junction. A “first-come, first-served” system has been in use in the Channel Islands for more than 30 years under the name of “filter-in-turn”. It costs less than a mini-roundabout, gives less delay, has as much capacity, and avoids the excessive delays that occur at roundabouts when a predominant stream on the circulatory roadway prevents vehicles from entering. Called by the Federal Highway Administration the safest type of intersection control, a “first-come, first-served” system used in the USA, the ALLWAY-STOP, cut accidents by half.6Serious accidents are very rare. The DfT amended the Traffic Signs Regulations and General Directives to prohibit the use of “first-come, first-served” systems, claiming they confused drivers.

Mini- and other roundabouts are also safer than traffic signals.7  They have cut accidents by half and serious-injury and fatal accidents by 60 to 90 percent worldwide.8   Mini-roundabouts also have a higher capacity than traffic signals.9, 10   The first mini-roundabout installed on a public road in 1968 in Peterborough replaced a set of signals and raised capacity by 27%.11   Enlarging a roundabout can increase its capacity further without a need to widen the road along its entire length, as is commonly done under traffic signal control.12

As there is no statutory requirement in the UK to assign priority to one road or another, junctions may be operated without any control whatever, just as happens when traffic signals suffer power failure.

Ten years of traffic management in Friesland in The Netherlands have shown that running traffic at 30 kilometres per hour, eliminating signals and other controls in urban areas ― and leaving road-users to their own devices and to their common law duty of reasonable care ― has cut accidents, delay and congestion, and saved public funds.13   So successful were those trials that other European towns are copying them.14

Verdict: Today’s traffic control system does not move traffic safely and expeditiously with minimal negative environmental impact and at an economic cost to the road-user and taxpayer. It causes accidents, delay and congestion. The system does not fit the purpose of efficient or safe traffic management.

Eliminating the misconceptions of the 1920s and managing traffic in line with common law principles will improve safety and relieve congestion at minimal cost.


1. 39 Am Jur 2d, Highways, Streets and Bridges, § 184, 1999

2. National Signal Timing Optimization Project. FHWA, 1982, 1

3. The Control of Traffic on Roads. Royal Commission on Transport, HMSO, 1929.

4. Harris, G. “Modern Traffic Control.” Highway sand Bridges, June 19, 1934, 6-9

5. K. Ogden, K., S Newstead, P Ryan and S Gantzer. Factors Affecting Crashes at Signalised  Intersections. Monash University Accident Research Centre, 1994.

6. Traffic Control Devices Handbook. FHWA, 2001, Chapter 10, 263.

7. Kennedy, JV, RD Hall and SR Barnard. Accidents at urban mini-roundabouts. TRL Report 281, 1998.

8. Persaud, B. N., R. A. Retting, P. E. Garder and D. Lord. Crash Reductions Following Installation of 

Roundabouts in the United States. Insurance Institute for Highway Safety, May 2000.

9. Mini-roundabouts in England and Wales. Surveyors Society, 1972.

10. Blackmore, FC. “Priority at Roundabouts.” Traffic Engineering & Control, June 1963, 104-106.

11. Blackmore, FC. Capacity of single-level intersections. RRL LR 356, 1970.

12. Millard, R. S. “Roundabouts and Signals.”  Traffic Engineering & Control, May 1971, 13-15.

13. “Safer with the lights out.” The Times, July 8, 2002.

14. “European Cities do away with Traffic Signs”. Der Spiegel (Germany). 16 November 2006 (translated) or c/o