O'Donnell Developments Ltd V Buildability Ltd

The adjudicator's application of the slip rule to correct the accidental error in his decision was made within his jurisdiction and the court could not and should interfere with it and even if the court could interfere, the error was an "inadvertent slip" and should not be interfered with



Technology and Construction Court
Ramsey J
18 December 2009

The adjudicator in his decision determined that the sub-contractor was entitled to payment in respect of the gross cumulative total value of the sub-contract works up to valuation 25 less payments to date. The sub-contractor notified the adjudicator of what it considered to an error in the decision, namely that the adjudicator, in calculating the sum due after deducting payments to date, included in his figure for the total of the payments to be deducted from the value of the works a sum paid for loss and expense awarded in another adjudication. The contractor objected to the correction of this error on the ground that it did not fall within the definition of slips which it was permissible for the adjudicator to correct. The adjudicator, however, stated that he did have power to correct the error and therefore issued a corrected version of his decision entitling the sub-contractor to this (additional) sum on the basis that his errors did not reflect his intention when formulating his decision.


Ramsey J held that the adjudicator's application of the slip rule was made within his jurisdiction and that the court could not and should interfere with the exercise of his powers to correct the slip within his jurisdiction. This was on the basis that to do so where the adjudicator was asked to correct a slip and accepted that he had made an error within the slip rule would be to seek to interfere in a case notwithstanding that the adjudicator had answered the right question and that the adjudicator’s decision would be temporarily binding, whether he was right or wrong in the answer he gave. Even if the court could interfere with the adjudicator’s exercise of his powers to correct the slip, he was correct to have identified the mistake he made as an "inadvertent slip" on the basis that he made a deduction which he had not intended to make and this was not a case of the adjudicator giving effect to second thoughts or intentions but was one of him giving proper effect to his first thoughts.