[2006] CSOH 3, 12 January 2006. A was the sub-contractor for ground, concrete and drainage, where T was main contractor. A made interim applications to T for payments for five items, one of which was for overtime working. When T refused payment, A referred the matter to adjudication. The adjudicator made awards to A in respect of each item. T continued to refuse to make payment, and argued that, so far as the overtime payments were concerned, the adjudicator had based his decision on the grounds that T had given verbal instructions to A to carry out the work at weekends, or alternatively T had acquiesced in A carrying out the work; at no time before the decision was issued, however, were these matters raised or discussed before the adjudicator. To decide the dispute on this basis was a breach of natural justice, as T had no notice of this or an opportunity to respond. "Held": adjudicators had to observe the principles of natural justice in reaching their decisions. If they behave in a manner which objectively involves a disregard of fair play and which appears to have a substantial and material effect on their decision, then the court must intervene. In this case, from the evidence, there had been such a clear and substantial breach of natural justice. Judgment was given for T.