Lahey v Pirelli Tyres Ltd [2007] EWCA Civ 91, [2007] All ER (D) 165 (Feb)
The effect of CPR 36.13(1) and (4) is that, upon acceptance of the Pt 36 payment, a costs order is deemed to have been made on the standard basis. That means that the claimant is entitled to 100% of the assessed costs ie the amount that the costs judge decides is payable at the conclusion of the detailed assessment.
The costs judge has no power to vary that order and so has no jurisdiction, at the outset of a detailed assessment of costs, to order that a paying party has to pay only a proportion of the costs that are ultimately assessed to be payable. However, in an appropriate case, the costs judge may disallow entire sections of a bill of costs on the footing that they were unreasonably incurred.