In Northern Ireland the Department for Regional Development (DRD), which incorporates the Roads Service of Northern Ireland, has overall responsibility for maintaining and inspecting adopted footpaths and roads. In respect of a tripping hazard, generally speaking the DRD operate a '20mm intervention level' across Northern Ireland.
The courts in Northern Ireland have generally accepted this practice as reasonable and have adopted the 20mm intervention level as the benchmark on an actionable defect. More particularly in the case of McArdle v DRD (2005) J Higgins, in dismissing a claim involving a tripping edge of 12mm stated that the 20mm standard "in the majority of cases ... is sufficient to determine whether there exists an actionable defect or not."
While the 20mm does offer a degree of clarity, the courts in Northern Ireland have determined in a number of cases that a tripping edge of less than 20mm can also constitute as an actionable defect. The courts here have advised that "an unthinking adherence to a 20mm policy" (J Kerr in Austin v DoE) makes no allowance for the differing conditions of individual roads and pavements. Thus on a number of occasions , the courts have determined that defects of less than 20mm can be "real sources of danger " .
It is apparent through these judgements that each case will be viewed on its individual facts and in particular there are a number of factors that the court will take into consideration in determining if a defect is actionable, such as;
In Austin v DOE (1993) the Plaintiff claimed for personal injuries which arose when the Plaintiff tripped on a raised flagstone edge, which was less than 20mm. In this case J Kerr gave judgment in favour of the Plaintiff, stating:
"I consider that the state of the footpath as seen in the three different sets of photographs was such that even though the raised edge was below the 20 millimetre standard and only covered a small part of the footpath, it was such as ought to have been recorded by Mr McCorry, the roads maintenance officer and referred by him if necessary to the professional technical officer to enable him to make the decision, which in my opinion ought to have been made, that repairs should be carried out to that section of the footpath. "
In the case of McClenaghan v DOE (1996 ) the Plaintiff once again claimed personal injuries which arose when she tripped on a raised part of the footpath which was les than 20mm. J Girvan stated:
"The determination of the question whether the road was dangerous is a question of fact and degree the test of dangerousness being objective ...."
Girvan J chose to adopt the 'test of reasonableness' that had been previously set out by Lord Denning in Morton v Wheeler:
"If a reasonable man, taking such contingencies into account, and giving close attention to the state of affairs, would say 'I think there is quite a chance that someone going along the road may be injured if this stays as it is', then it is a danger; but if the possibility of injury is so remote that he would dismiss it out of hand saying of course it is possible but not in the least probable, then it is not a danger".
There is some gap in the degree of publically available information in Northern Ireland setting out the intervention and repair procedures of the DRD ; however some guidance can be gleaned from the response provided by the Minister of the DRD to a question raised at the Northern Ireland Assembly in 2001 on the policy of road maintenance and in particular the repair of pot holes and also discussed any performance criteria used by the DRD regarding the estimated time for the repair of such faults.
The Minister advised that it was the DRD's objective to repair or make safe within 1 day of detention 90% of defects above 50mm and within 5 days of detection 90% of defects between 20mm and 50mm on heavily trafficked urban roads and footpaths. In terms of inspection town centres and major traffic routes should be inspected on a monthly basis and all other roads and footways are due to be inspected at either 2 or 4 monthly intervals.
The courts have accepted this level of intervention and and inspection as reasonable and one which facilitates the statutory defence argument raised by the department (under Article 8 of the Roads (NI) Order 1993 ) . However, as we have seen if a defect is less than 20mm but represents, in all the circumstances as a "danger" the courts will expect the DRD to note this on inspection, intervene and repair the defect.