Highway Authorities' duty in respect of potholes

AC & DC v TR & Devon County Council
High Court - 29 March 2012

Slade J has reviewed the law involved in applying Sections 41 and 58 of the Highways Act 1980 to a case in which a serious road accident was caused by a length of potholing in the road. John Morrell, Director, Local Authority team, takes an in-depth look at the judgment and the court’s reasoning in finding Devon County Council liable for the accident.


TR was driving a Land Rover along the C25 road near Honiton in November 2006.  As he went to overtake the vehicle in front, the offside wheels of his vehicle entered an area of potholing whereby the edge of the metalled carriageway had been indented, and he lost control of his vehicle.  In steering to correct the situation the vehicle crossed the carriageway and struck a tree causing very serious injuries to the passengers.  TR admitted liability for the accident and his insurers agreed damages to be paid to the passengers amounting to several million pounds.  TR claimed an indemnity or contribution from Devon County Council (“the Council”) as highway authority alleging that it had failed to maintain the highway under Section 41 of the Highways Act 1980 (“HA”).


Was there a failure to maintain the highway under Section 41 of the Highways Act 1980?

The evidence was that this was a rural road with soft verges.  It was used by heavy vehicles and agricultural plant, which was known to override the edge of the carriageway causing damage to the metalled edge of the carriageway.  Where the accident happened the potholing or intrusion extended from the edge of the carriageway about 150mm into the road and went to a depth of more than 80mm.  There was a white line at the edge of both sides of the carriageway which was, in places, obscured, or partly obscured, by the intruding potholes.  The offside wheels of TR’s vehicle probably entered the potholed area before the point of maximum intrusion into the edge of the carriageway and then travelled along the potholed area for a short period before the vehicle crossed to the other side of the road.

The Council had an intervention level of 100mm for overriding damage at the edge of the carriageway and it was possible that the damage at this location did not reach that intervention level, however, the Council accepted that if this area of potholing had been seen by a highway inspector it would have been repaired.  Slade J considered the test of dangerousness which has been applied by courts in the past and in particular she referred to the following:

  • The test of dangerousness is one of reasonable foresight of harm to users of the highway…But in drawing the inference of dangerousness the court must not set too high a standard.” – James & Thomas v Preseli Pembrokeshire DC (1992).
  • “The highway has to be maintained in such a state of repair that it is reasonably passable for the ordinary traffic of the neighbourhood without danger caused by its physical condition.” –Jones v Rhondda Cynon Taff CBC (2008).

Slade J concluded that the combined overriding and pothole damage at the edge of the carriageway rendered the part of the highway, where TR’s vehicle encountered it, dangerous to traffic.  Although not many drivers would drive outside the white line at the edge of the carriageway it was foreseeable that some would, particularly when overtaking, and it was foreseeable that a car driven on the edge of the carriageway in this location would encounter the damaged edge.  Accordingly Slade J concluded that the damage to the edge of the carriageway did amount to a failure to maintain the highway under HA Section 41.

Did Devon County Council have a defence under Section 58 of the Highways Act 1980?

The Council scheduled the road for inspection every six months.  On the other hand the relevant Code of Practice issued by the Department of Transport recommended inspection of this type of road on a monthly basis.  The Code of Practice in force at the time was not mandatory on highway authorities, however, Slade J relied on it in detail.  In particular, she noted that where a highway authority elects, in the light of circumstances, to adopt standards which differ from the Code of Practice, the Code stated that:

It is essential for these to be identified, together with the reasoning for such differences.

The evidence accepted by Slade J was that the decision to inspect this road on a six monthly basis seemed to be of long standing.  There was no record of any consideration or review of the highway inspection regime by the Council.  The one document which was produced by the Council said that its system complied with the Code of Practice because traffic flows were generally lower than the parameters in the Code of Practice, but the Judge noted that no traffic survey was carried out until some time after the accident.

The Code of Practice pointed to various factors which a highway authority should take into account, such as traffic use, characteristics and trends, incident and inspection history, characteristics of the adjoining network and wider policy or operational considerations.  Slade J considered that there was no evidence that the Council had considered these points.  Although evidence was given that increasing the frequency of inspections from six monthly to monthly would add an extra cost of £23,000 to the highways budget, the Judge noted that this represented only 0.03% an overall budget of £71 million.  Furthermore, the Council produced evidence that other highway authorities inspected similar roads on a six monthly basis, however, the basis on which such authorities had made their decisions was unclear.  Furthermore, Slade J noted that when this particular road entered the neighbouring area of Somerset County Council, that Council inspected the road every three months.

In the circumstances, Slade J concluded that the Council had not established that a six monthly maintenance regime for the type of road in question was appropriate.


Slade J accepted that if the Council could show that a monthly inspection regime would not have detected the defective carriageway then the fact that the Council could not establish a defence under HA Section 58 would make no difference.  There was evidence that some potholes could appear overnight, however, the Judge noted that the potholing here was at least 80mm deep and accordingly she concluded that this would have taken longer to develop.  She considered that it was likely that the damage had been caused by overriding of the edge of the carriageway by vehicles at harvest time, namely a number of weeks before the accident.  The lack of a monthly inspection regime was therefore causative of the accident.

Repair or improvement?

There was evidence that a more permanent means of repairing the edge of a carriageway abutting soft verges was available to the Council by means of what was called “haunching”.  Slade J considered, however, that the decision in Stovin v Wise (1996) made it clear that it was not appropriate for the court to adjudicate on what would amount to an improvement to the edge of the carriageway rather than maintenance.

Contributory negligence

TR admitted liability for the accident.  The Judge considered, however, that even though TR probably drove beyond the white carriageway edge line during the overtaking manoeuvre, and reacted to the wheels of his vehicle entering the potholed area by over steering more than was necessary, he did not display a lack of reasonable care.  Accordingly, he was not contributorily at fault for the accident.


It seems clear, first, that courts are prepared to differentiate between defects at the edge of the carriageway, and defects at the edge of a pavement, when considering whether there has been a failure to maintain the highway under HA Section 41.  It is to be foreseen that vehicles might drive on or over the edge of the carriageway while pedestrians should be able to avoid the edge of the pavement or footpath provided it is sufficiently wide.

In dealing with the defence under HA Section 58, it seems likely that the Council had in mind the Court of Appeal decision in Wilkinson v City of York Council (2011).  In that case, the Court of Appeal held that in departing from the inspection regime recommended by the Code of Practice, highway authorities should carry out a risk assessment and not simply rely on evidence of the extra cost involved to the highways budget.  Here the Council referred to lower traffic use and also tried to rely on evidence from other highway authorities, however, the Judge considered that the Council had not done enough to establish that it had considered the relevant issues when deciding on the inspection regime.

Finally, when looking at contributory negligence, perhaps the Council might count itself hard done by.  TR accepted liability for the accident and thereby accepted that his driving had fallen below the appropriate standard but the Judge still held that the Council should bear 100% responsibility for the accident.

For further information please contact John Morrell, Director, Local Authority team on 0207 645 9538 or at

This information is intended as a general discussion surrounding the topics covered and is for guidance purposes only. It does not constitute legal advice and should not be regarded as a substitute for taking legal advice. DWF is not responsible for any activity undertaken based on this information.

Perry Hill


I am a partner in the insurance team in the London Office. I specialise in defending high value personal injury claims particularly those brought against local authorities, police services and schools.

Mark Whittaker

Partner - Head of Casualty and Occupational Health Team (London)

I am a London based partner and head of the Occupational Health and Casualty team, within the firm’s leading Insurance team.