Flintshire County Council has been found guilty of maladministration over an unlawful planning development after an Ombudsman investigation.

Maladministration on the part of Flintshire County Council’s planning department as local planning authority (LPA), caused injustice to the person living in the next door property, the Ombudsman report found.

The report, which has been anonymised to protect the identity of the complainant and the location, found the development proposed by a Certificate of Lawfulness of Proposed Use or Development (a “s192 certificate” for an “annexe” containing primary living accommodation to be built in the garden of the next-door property) was not within a class for which planning permission was not required. It adds that it was thus not lawful development and the application should therefore not have been granted.

When a retrospective application was made to retain the development (which had not been built in accordance with the s192 certificate) the planning officer had been influenced by the existence of the wrongly granted s192 certificate and the Ombudsman found that it was unlikely that permission would have been granted in its absence.

The Ombudsman upheld the complaint, saying there was maladministration, both in the grant of the s192 certificate and in the grant of the retrospective application.

The Local Planning Authority's actions caused “significant injustice” to the next door neighbour - called Ms N in the report.

Public Services Ombudsman for Wales, Nick Bennett, said: “As a whole, the failings which I have identified mean that Ms N has suffered a significant loss of privacy in both her home and garden, which has affected the enjoyment of her home.”

“In addition, the existence of what is in effect a new house built in the garden of the house next door to her property is likely to have diminished the character and value of her home. The situation caused her immense stress, which I can only conclude is a significant injustice to Ms N.”

The Ombudsman has made a number of recommendations including that the council apologise to Ms N for the failings identified, and review whether the conditions attached to the retrospective permission had been complied with.

He also recommended that the council instruct the District Valuer to assess the impact of the development on the complainant's property and pay them the difference in the value of her property before and after the development.

A Flintshire County Council spokesperson said the authority could not comment before councillors had the opportunity to consider the report on May 28.

They said: "The Public Services Ombudsman for Wales has issued this report in response to a complaint about the grant of planning permission for an annexe in the back garden of a resident’s property.

"Where a report such as this makes a finding of maladministration the council is under a duty to publicise the report and to formally consider the findings and recommendations at a Council meeting.

"Full Council will therefore make the final decision on whether to accept the findings and/or recommendations. It will do so at its meeting on 28 May. Until all councillors have had an opportunity to consider the report, it is not appropriate to comment on the issues in the case.