Wallis v Bristol Water Plc

In a penal provision, likely does not invariably mean more probable than not. Its meaning depends on the statutory context and legislative purpose. In regulations protecting the public water supply from contamination, it means a real possibility which cannot sensibly be ignored having regard to the nature and gravity of the feared harm. The court may therefore consider both the likelihood of contamination and the seriousness of its consequences. The criminal character of the provision does not require an interpretation which would substantially undermine its protective purpose. A pre-existing lawful installation may nevertheless be required to have backflow protection where the regulations permit the water undertaker to give an appropriate notice.

The claimant appealed by way of case stated against convictions before justices for six offences under regulation 3(2)(i) of the Water Supply (Water Fittings) Regulations 1999. The charges concerned hose union taps and an udder wash on a dairy farm, installed or used without the required backflow protection. The justices found that the fittings were likely to cause contamination of the public water supply and imposed fines, a surcharge and costs.

The questions were whether the fittings were likely to cause contamination, whether the regulation 2(4) protection for pre-1999 installations was displaced by notice under Schedule 2, paragraph 15(4)(b), and whether the criminal standard had been correctly applied.

The court, consisting of Lord Justice Dyson and Mr Justice Tugendhat, dismissed the appeal and answered all three questions in the affirmative.

1. Meaning of likely. The word must be construed in the context of the regulations as a whole and in light of their purpose. The regulations implement the protective purpose of section 74(1) of the Water Industry Act 1991, namely preventing contamination of water and protecting public health. In that context, “likely” means a real possibility which cannot sensibly be ignored having regard to the nature and gravity of the feared harm.
2. The justices were entitled to consider both the probability of backflow contamination and the potentially catastrophic consequences for public health. A fitting directly connected to the mains and designed for hose use could remain dangerous even though a hose was not attached at the inspection, and an assurance that a hose would not be used was not sufficient protection.
3. The criminal nature of regulation 3(2) did not require “likely” to mean probable. Although ambiguity in a penal provision will generally be construed in favour of a defendant, that principle is subject to the statutory context and legislative purpose. Applying a probability threshold would substantially undermine the protective purpose of the regulations.
4. Pre-existing installations. Regulation 2(4) protects fittings lawfully installed or used before 1 July 1999 from the general retrospective operation of the regulations. It does not prevent the water undertaker from requiring backflow prevention by notice under Schedule 2, paragraph 15(4)(b). The notice concerning the udder wash was therefore authorised and justified, and an isolating stop tap was insufficient because it could be turned on again.

The appeal was dismissed. The court declined to make a summary assessment of the respondent’s costs; costs were to be subject to detailed assessment if not agreed.

• High Court (Administrative Court): On a case stated from the justices, the court answered all three questions in the affirmative and dismissed the appeal.