Build Ability Limited (“BAL”) was the main contractor of a mixed retail and leisure development in Birmingham. O’Donnell Developments Limited (“ODD”) was engaged as a concrete framework contractor. The contract was an amended DOM/2 Form of Sub-Contract (1981).

 

This hearing concerned two adjudications. Adjudication 8A concerned the value of the sub-contract works up to Interim Valuation 25. The Adjudicator decided that ODD was entitled to £14,328,131.88 less retention, valid BAL deductions and payments to date. A day after the Adjudicator’s decision ODD notified the Adjudicator of two errors: (1) that he had incorrectly included in the payments to date a sum which had been awarded in Adjudication 7 (i.e. after the date of Valuation 25); and (2) that the retention was miscalculated.

 

BAL objected to the correction of these errors on the grounds that they did not fall within what was permitted by the slip rule. The Adjudicator considered that he had power to correct the errors and revised his decision.

 

In a subsequent adjudication the Adjudicator awarded BAL a further £285,306.56. BAL declined to pay the sums awarded in the two adjudications.

 

At the subsequent enforcement hearing, BAL contended that the Adjudicator’s calculations were based on figures provided by ODD and he was induced by those figures, therefore this fell outside what could be defined as a slip. ODD argued that it did fall within the slip rule because the incorrect Adjudication 8A decision did not accurately reflect his true intentions. The Judge agreed.

 

The Judge decided that, if there were an express or implied term in the contract, an adjudicator could correct an accidental error or omission provided it is done in a reasonable time. Furthermore, an adjudicator exercising its powers erroneously does not mean it is acting outside of its jurisdiction. The distinction between disputes as to an adjudicator’s jurisdiction and disputes as to ways in which that jurisdiction should be exercised is not an easy one to draw:

 

 

The Judge also said that courts should be careful not to mischaracterise a mistaken application of the slip rule as being outside of an adjudicator’s jurisdiction. Therefore in this case the slip rule was an accepted implied term of the contract. The Adjudicator was asked to correct a slip and, though he had made an error within the slip rule, he was not acting outside of his jurisdiction.

 

Even if the Judge were wrong, he decided on the merits of the case that the Adjudicator had made an inadvertent slip as by making a deduction which he had not intended to make this was within the slip rule. Notwithstanding that the mistake had been made as a result of erroneous information provided by ODD, this was not uncommon and did not prevent an adjudicator from concluding what he has done is not what he intended.