Road Network Operations
& Intelligent Transport Systems
A guide for practitioners!

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Liability in the legal sense concerns responsibility by an individual, enterprise other organisation for its actions and the conduct of its contractual obligations.

“Legal liability can arise from various areas of law, such as contracts, tort judgments or settlements, taxes, or fines given by government agencies”. (Wikipedia)

The legal liabilities of authorities and commercial companies that provide ITS services and equipment can arise in many different ways. Proper consideration of liability implications should form part of the planning of any ITS implementation as well as the design and manufacture of any ITS components. The more an ITS application is automated or “authoritative” in the advice it issues, the more it replaces the need for actions or decisions by users, diluting their responsibility and liability. Many everyday ITS installations are safety critical – such as the advisory signal system illustrated in the figure below.

Advisory signals for cyclists and pedestrians

The allocation of responsibility when something goes wrong can become more blurred. The balance of liability between the ITS user, developer or provider is open to debate and may change – either through case law establishing new legal precedents or through new legislation being enacted.

The United Nations Vienna Convention on Road Traffic (1968) requires that every moving vehicle or combination of vehicles shall have a driver, and that the driver shall at all times be able to control the vehicle. These requirements are fundamental principles of liability in road traffic scenarios. As ITS evolves into a “systems of systems” – with information inputs from many different sources being processed and turned into advice, commands or automatic actions in-vehicle – the question of liability becomes less clear cut. On-road testing of cooperative systems and autonomous vehicles is happening now and the time is fast approaching when the framework for road traffic liability may need to be revised.

Liability issues are often cited as a barrier to the deployment of future ITS applications such as autonomous vehicles and cooperative systems. (See Driver Support and ITS Futures) It is worth remembering that similar concerns were voiced in the past about Advanced Driver Assistance Systems (ADAS) such as assisted braking or assisted parking and whether they would lead to large numbers of liability lawsuits. These systems are now in full production because the automotive industry was satisfied that the liability risks were outweighed by the benefits and commercial returns. The same judgements have been made in relation to Intelligent Speed Adaptation (ISA) (See Intelligent Speed Adaptation), which is now deployed in public fleets in several countries.

A pattern emerges from the examples above, which suggests that any ITS development that reduces the need for actions or decisions by the user or transport provider should be subject to a risk assessment. It will only be successful in the market – achieving widespread acceptability – when public confidence is won.

Most countries will have a legal liability regime that will impact on ITS implementations. This can vary between countries and regions. Sometimes the law and accepted practice will be in harmony, and sometimes they may conflict. When considering the liability issues of an ITS implementation, the regulatory framework needs to be taken into account to make sure that legal liability is not overlooked.

Product liability

The universal principles most broadly adopted are that a product:

  • has to be fit for purpose
  • its description has to be truthful and fair
  • its manufacturer and seller (in the case of ITS) must have a reasonable grasp of the latest technical developments and performance information and must have applied this knowledge to the design of the product (the State of the Art principle)

While conditions of usage and disclaimers can be used in a contract, these cannot remove the right of the user or purchaser to expect the product to perform to a reasonable standard.

An ITS example

A highways authority may purchase traffic signalling equipment and then argue that its breakdown rate is unacceptably high, seeking redress from the supplier. In mitigation, the supplier may point out that:

  • other similar equipment has similar breakdown rates
  • the equipment was badly installed by others
  • the authority is using the equipment for purposes it has been told are inappropriate
  • the authority has failed to follow the recommended maintenance regime
  • disclaimers in the contract of sale (See Procurement and Competition)


The legal definition of negligence, and how negligence is dealt with in law, varies from country to country. As a general principle, a charge of negligence in ITS implies that the provider of a service or product has breached a duty of care to the customer or user, who has suffered injury or loss. The burden of proof is applied in different ways and to different stakeholders in different countries – and the definition of what constitutes “loss” can also be different. A good guide for an ITS implementer is to look at previous legal cases involving allegations of negligence in their country – to draw informed conclusions about how to avoid similar problems arising when their ITS is deployed. It is difficult to think of an everyday case within ITS where negligence could be proved in the current legal and policy situation. This may change if ITS cooperative systems (See ITS Futures) become widespread – since here the driver is much more dependent on the actions of others, whose duty of care to the driver becomes correspondingly greater.

ITS examples

a driver may argue that they were injured in a crash which would have been avoided if the highway authority had adequately informed him via Variable Message Signs or radio messages of poor road conditions – perhaps icy road surface or poor visibility. This would normally fail, as the court is unlikely to agree that the road operator’s duty of care to the driver extends this far – determining instead that drivers are responsible for monitoring road and weather conditions themselves:

a train passenger may argue that the fare paid is too much because the train operator did not provide adequate information about cheaper tickets available. This too would most likely fail, for the same reason.

Contractual liability

In ITS, contract law will usually apply to an authority purchasing a service from a provider, and to the purchase of ITS equipment. In the case of navigation systems (See Driver Support) and ADAS, the purchaser would be an individual person. A contract relating to ITS is enforced in the same way as any other contract. Disclaimers and other statements in the contract intending to limit the liability of either party will only be enforceable if they can be considered to be reasonable, fair, and compatible with related principles such as duty of care.

ITS examples

a driver may purchase a navigation system and use it for work as a lorry driver. If the system regularly redirects the driver to routes unsuitable for the vehicle, the driver may regard the product as defective and seek redress. The challenge will be unsuccessful if the product was intended for private car use rather than use in a lorry. A challenge would only be successful if it could be proven that the navigation system was designed specifically for use in a lorry of the size and class used

a public transport operator (See Passenger Transport) may contract with a service provider to process its ticketing transactions, with the contract stating that 98% of transactions will be correctly processed. If spot-checks and customer complaints show that in fact only 85% of transactions are correctly processed, a claim by the operator against the service provider is likely to succeed. However, the service provider will try to identify and prove failings by their customer as mitigation – such as wrong passenger information or failure of customer-owned equipment.

Traffic and transport legislation

This is usually more of a background consideration when considering liability in ITS – but it does need to be taken into account. An example is those countries where fault automatically lies with the vehicle driver if a vehicle collides with a pedestrian or cyclist. This can lead to a complex situation if any of the parties in the collision were being influenced by an ITS implementation which failed to work properly.

Cooperative Systems

From the 1980s onward, when use of ITS became mainstream, there have been surprisingly few examples of litigation regarding liability in the area of ITS, as compared with the level of nervousness and uncertainty that the issue generates. This is likely to be, in part, because all parties have taken due care in assessing the risks and benefits. It is also helped by the flexibility of legal systems to apply basic principles (such as reasonableness or proportionality) to situations involving new and complex technical applications.

We are now at the stage where on-road implementations of cooperative systems and autonomous vehicles (See ITS Futures) appear certain to become a reality in some countries over the next ten years. Once the systems control the activities of vehicles – with no realistic chance of a timely human intervention – it may be appropriate to move liability to the system providers and the information providers who serve them.

Some cite the Vienna Convention (1968) as a barrier to these developments. It is far more likely that the safety and environmental benefits of cooperative systems and autonomous vehicles are attractive enough to create a consensus that its principles will have to be modified.

Advice to Practitioners

The area of liability in ITS is complex, but with the possible exception of autonomous and cooperative systems that are making the transfer from research to full-scale deployments, it is no more complex than liability in other sectors. Many people become concerned with liability issues when:

Risk and impact assessment of new and updated ITS must always address liability issues. This should be formalised in the process, so that lessons learnt are carried forward from one implementation to the next.

It is also important to seek appropriate professional legal advice. When implementing any specific ITS for the first time in a country, time spent discussing potential liability issues and working on solutions will repay itself many times over during the lifetime of the ITS. A specialist in national liability law will be able to identify the potential issues, and the ITS practitioner will almost always know how to mitigate them once they have been pointed out.

In countries with well-established ITS, there is usually a small number of legal experts specialising in ITS issues. These are well placed to comment on complex issues. In developing economies, a general liability specialist will usually have the knowledge and expertise needed.

Where other countries have already demonstrated that an ITS implementation can be undertaken and no significant liability issues arise – practitioners should feel confident that if they proceed with due regard for relevant national legislation, they too should be able to avoid these problems.

Those considering pioneering use of ITS – not yet tried on-road elsewhere – should proceed with caution and give as much weight to liability issues as to ITS technology.



Reference sources

Directorate-General for Mobility and Transport. (2011) Intelligent Transport Systems in Action. Brussels, European Commission.

Dumortier, J. 2012. The European Legal Framework for Automotive On-Board Networks. Vienna, Proceedings of the 2012 ITS World Congress.

Elliott, P. and Stanley, E. (2010) Liability Issues with Intelligent Transport Systems. Transport Engineering and Control (TEC) Magazine, February 2010.

Government Office for Science, 2011. British Roads Transformed by Intelligent Transport Systems. London, Department for Business Innovation and Skills.

Strang, D. 2005. ATT Related Accidents – Who’s Liable. London, Travers Smith Braithwaite.

Weimerskirch, A., Schramm, K., Wolleschensky, L. and Wollinger, T. 2009. The Dilemma of Data Security, Privacy, Control and Liability in V2XStockholm, Proceedings of the 2009 ITS World Congress.

Yen, R. 2012. ITS Action Plan – Action 5.2 – D6 – Final Report of the Study regarding liability aspects of ITS applications and services. Brussels, European Commission.