By Paul Davies and Michael Green

The public trust doctrine is the principle that certain natural and cultural assets are preserved for public use and that it is the government’s obligation to protect and regulate these, both now and for future generations. Although the doctrine is established in English common law, it is not regularly deployed by the English courts. However, a new piece of legislation, the Well-being of Future Generations (Wales) Act 2015 (WFA), geared towards improving the social, economic, environmental and cultural wellbeing of Wales, captures many of the values of the public trust doctrine. In particular, it focuses on the long term impact of public body decisions and how they should promote a good quality of life for both current and future generations.

The public trust doctrine was established in English common law when a form of it reappeared in the 12^th century, along with the onset of a more centralised legal system. One of the earliest cases is that of Juliana the Washerwoman (1299), in relation to a washerwoman who successfully challenged her powerful neighbour from cutting off her use of the watercourse. It was held that water had always been available for use by all, and that it was unlawful to pollute it. However, over time, the UK courts restricted the application of the public trust doctrine and it is now considered to do no more than give rise to a rebuttable presumption that the public has a right to fish, navigate and access the sea and tidal waterways. To date, these presumptions have not caused the state to actively take steps to protect public rights. However, many of the provisions of the WFA in fact impose positive obligations on public bodies so this arguably an effective implementation of the doctrine.