‘The lawfulness of any use, operations or other matter for which a certificate is in force under the section shall be conclusively presumed.’

Given that clear wording one would have thought that a certificate of lawful use would be conclusive and that you could therefore always rely upon it. But, it seems that is not the case, given that the High Court has recently held that it is possible to abandon a use under a certificate of lawful use. In the court’s view, a certificate of lawful use does no more than declare conclusively that a particular use is lawful – at a particular point in time. There is nothing to prevent that new use from being abandoned if the objective test for abandonment (under normal planning law) is satisfied. What this means in practical terms is that you cannot assume that a use definitely exists merely because there is a certificate of lawful use. You still need to make inquiries about how the property is actually used (eg periods of non-use and any alternative uses). Accordingly, be on your guard to ensure that you do not automatically assume that a certificate of lawful use guarantees the position. M&M v Secretary of State [2007] All ER (D) 55. © Practical Lawyer