Slip Rule in UK Law

The power cannot be used to change the substance of a judgment or order: further authorities are cited at CPR 40.12.1 in the White Book. It is because the judge can use the slip rule only to make his original meaning plain rather than to change his original decision, that the Civil Procedure Rules and the Tribunal's Procedural Rules contain no provision for consultation with the parties.

Those cases establish that the slip rule cannot enable a court to have second or additional thoughts. Once the order is drawn up any mistakes must be corrected by an appellate court. However it is possible under the slip rule to amend an order to give effect to the intention of the Court. If the last two cases referred to above had been cited in Molnlycke, I believe the obiter statement made by the judge would have been expressed differently.

The limitation discussed in the authorities, and which I think is what is meant by the sentence in the White Book, is that there should genuinely have been an accidental error or omission: the slip rule should not be used to permit the court to have second or additional thoughts or to add a provision having substantive effect which was not in the contemplation of the parties or the court at the hearing.

However, the distinction between disputes as to the jurisdiction of an adjudicator and disputes as to ways in which that jurisdiction should be exercised is not an easy one to draw as the decision in Lesotho Highlands shows. Finally, if the adjudicator is asked by one party to correct a slip which the other party agrees is a slip within the slip rule but in operating the slip rule he makes and error of fact or law, then I do not consider that the court can interfere in that decision.

In the present case it is accepted by BAL that the slip rule is an implied term of the Sub-Contract. The Adjudicator was asked to correct a slip and accepted that he had made an error within the slip rule. In such circumstances I do not consider that the court can or should interfere with the exercise of the adjudicator's powers within his jurisdiction.

7 My citation of Katsonga should not be taken as implying approval of the proposition in the judicially-drafted headnote that 7 My citation of Katsonga should not be taken as implying approval of the proposition in the judicially-drafted headnote that

It is the distinction between having second thoughts or intentions and correcting an award or judgment to give true effect to first thoughts or intentions, which creates the problem. Neither an arbitrator nor a judge can make any claim to infallibility. If he assesses the evidence wrongly or misconstrues or misappreciates the law, the resulting award or judgment will be erroneous, but it cannot be corrected either under section 17 or under Order 20 rule 11.