The Court of Appeal has usefully confirmed the validity of a Part 36 offer (Offer) made by a defendant which:
- Covered the claim and an as-yet unpleaded counterclaim.
- Provided for interest to accrue at 8% per annum post-expiry of the Relevant Period.
The claimant/appellant relied on Hertel v Saunders  EWCA Civ 1831, which post-dated the lower court’s judgment. However, Asplin LJ focused on Lloyd LJ’s obiter remarks in AF v BG  EWCA Civ 757 (paragraphs 17-21), including his apparent acceptance that an unpleaded counterclaim could be included in a Part 36 offer, because old CPR 36.3(2) (now CPR 36.7) allowed Part 36 offers to be made before commencement of proceedings.
As Lloyd LJ observed in AF v BG, under CPR 20.2 and 20.3, a counterclaim was generally treated as a claim for CPR purposes. The current CPR 36.2(3) made clear that CPR 20.2 and 20.3 applied for Part 36 purposes, and CPR 36.2(3)(a) allowed Part 36 offers to be made in respect of the whole or part of (or any issue that arose in) a claim, counterclaim or additional claim. Accordingly, Asplin LJ rejected the notion that a Part 36 offer could not be made in relation to an as-yet unpleaded counterclaim. CPR 36.5(1)(d) and (e) had to be construed so as to enable such an offer to be made.
Asplin LJ noted that AF v BG was not cited in Hertel. Further, Hertel was primarily concerned with the effect of old CPR 36.10(2) (no longer in the CPR) and considered a defendant’s offer relating to a proposed amendment to a claimant’s claim in existing proceedings.
The court also clarified (for the first time, we believe) that including a term as to interest post-expiry of the Relevant Period did not invalidate the Offer as a Part 36 offer. Nothing in CPR 36 precluded such a term, or terms additional to the CPR 36.5(2) requirements. If a party could not include interest in this way, they would not be compensated for any delay between expiry of the Relevant Period and a subsequent acceptance of the offer. Interest post-expiry of the Relevant Period was ignored under CPR 36.17 (Purrunsing v A’Court  EWHC 1528); it should also be ignored when determining whether a Part 36 offer is valid.
Case: Calonne Construction Ltd v Dawnus Southern Ltd  EWCA Civ 754 (3 May 2019) (Asplin, Flaux and Hamblen LJJ).
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