Readers dealing with enforcement matters will know that it is a matter of judgement for a local authority as to whether or not it is expedient to take enforcement action against a breach of planning legislation; the funds to pursue such action are, of course, drawn from the public purse.
Accordingly, such readers might find useful the following neat summary of the law on expediency, found in a recent appeal decision (DCS Number 400-013-325):
“The starting point in this regard is section 172(1)(b) of the 1990 Act as amended, which specifies that a notice may be issued when it appears to the local planning authority that it is expedient to do so, having regard to the provisions of the development plan and any other material considerations.……
Firstly, the Appellant’s argument in this regard is based solely on the notion that he should have been given the opportunity to make a planning application for some or all of the unauthorised works before enforcement action was pursued. However, even though this is often good practice it is not a statutory requirement and thus has no bearing on the legal standing of the enforcement notice.……
Secondly, the High Court found in R (Ardagh Glass Ltd) v Chester CC  that, as a test, ‘expedient’ suggests the balancing of the advantages and disadvantages of a course of action, the basis for which should be the assessment of planning considerations. The phrase ‘where it appears to them’ in section 172(1) is a clear indication that whether to issue an enforcement notice on this basis is a matter for the local planning authority’s discretion..…..
In any event, in the case of Britannia Assets v SSCLG & Medway Council  it was held that there was no jurisdiction for an Inspector to determine whether or not the local planning authority had complied with its obligation under section 172 in this regard. Any legal implications of whether it was ‘expedient’ for the authority to issue an enforcement notice are therefore matters to be dealt with by way of judicial review.”
The following DCP section is relevant: 4.5313