Expert evidence is a critical part of environmental litigation and the problems of expense, delay and complexity in civil litigation, which Lord Woolf's Access to Justice report identified, can be exacerbated in such cases. Experts can reasonably differ not only over factual information, such as how much of a contaminant is present and how it got there, but over causation issues, such as whether a particular injury resulted from exposure to a particular contaminant.
Few practitioners would deny that expert evidence can cause difficulties, particularly when judges are faced with a proliferation of conflicting but plausible experts. But whether one endorses Woolf's suggestions is quite a different matter.
Such concerns did not seem to worry the new contaminated land liability regime, the Environment Act 1995, which builds on the Environmental Protection Act 1990, and will probably come into force later this year or early next year.
The legislation assumes it will be possible to ascertain a number of technical issues about contamination, and makes clear there is a role for expert evidence. But it only provides for appeal to the magistrates court, which is governed by very different procedures from those for civil litigation. Even if Woolf's reforms are adopted, they will not apply to cases heard in a magistrates court.
But expert evidence is vital to enable the new contaminated land provisions to function. Conclusions on liability are made on the basis of an understanding of the contamination and its effects (or potential effects), which depends upon expertise in risk assessment and the clean-up of contaminated land. And the new system is based on a local authority believing land meets the statutory definition of contamination.
The definition of contamination (in section 78A) refers to land which a local authority believes is in a condition whereby significant harm is being caused (or there is a significant possibility of harm being caused), or pollution of controlled waters is being caused (or is likely to be caused) as a result of substances in, on, or under the land.
Although there will be guidance from the Secretary of State which an authority must follow when making its decision, there is scope for expert evidence on links between the substances, and the harm, the significance of any harm and the likelihood of harm being caused. The expert evidence will consist of both fact and opinion.
After an authority has decided it has a contamination case, a remediation notice will be served on the appropriate person to bear liability. Appeals by recipients of notices can be anticipated on several grounds: that the contamination criteria in the legislation are not met; that other persons should have been served instead of, or as well as, the recipient; that liability was incorrectly apportioned among recipients; or that the notice demands more extensive remediation than is appropriate under the legislation.
If this were not difficult enough, the legislation introduces further layers of technical information requirements. For example, a remediation notice can only require actions which the local authority considers reasonable in the light of matters such as the likely cost involved and the seriousness of the pollution in question. And since the provisions relate to past events, the key question of liability will often hinge on events which took place over a number of years or occurred many years ago.
It remains to be seen how the contaminated land provisions will work in practice. The Government's stance has been that it simply represents the application of established principles of liability – the law over statutory nuisance, for example – to contaminated land situations.
However, legislation giving a mandate to local authorities to inspect for contaminated land and secure remedial action seems likely to result in a greater risk of liability. In addition, the Government's goal of an equitable and efficient system, in that remediation is only required where actual risks exist, has led to a daunting and technically complex system.
Magistrates, presumably including lay benches, will be presented with cases involving complex expert evidence and will experience the problems which Woolf identified and have preoccupied more experienced High Court judges. A year or two from now, they may see it as ironic that the contaminated land regime was introduced at a time when Woolf was trying to overcome the same expert evidence issues.