158. (1) Subject to section 160, the determination of a Legal Costs Adjudicator is final and shall take effect 20 days after it is furnished under section 157(2) to the parties to the adjudication.

(2) Where an adjudication concerns only legal costs as between a legal practitioner and his or her client, and the Legal Costs Adjudicator has determined that the aggregate of the amounts to be paid is less than 15 per cent lower than the aggregate of those amounts set out in the bill of costs, the party chargeable to those costs shall pay the costs of the adjudication.

(3) Where a Legal Costs Adjudicator has determined that the aggregate of the amounts to be paid in respect of the legal costs referred to in subsection (2) is 15 per cent or more than 15 per cent lower than the aggregate of those amounts set out in the bill of costs, the legal practitioner who issued the bill of costs shall be responsible for the costs of the adjudication.

(4) Where subsection (3) applies, the Legal Costs Adjudicator may determine that the costs of the adjudication be set-off against the aggregate amount determined.