In this article, Duran Ross and Nicola Thompson examine the decision in Grijns v Grijns [2025] EWHC 2853 (Ch) which provides a detailed analysis of the costs consequences following a party's conduct regarding alternative dispute resolution (ADR).
This article first appeared on the Practical Law Dispute Resolution column on 30 January 2026. Reproduced from Practical Law with the permission of the publishers. For further information visit www.practicallaw.com.
The High Court's judgment in Grijns v Grijns [2025] EWHC 2853 (Ch) provides interesting analysis by the court of the costs consequences of failure to mediate in a hard-fought intra-family property dispute. The court awarded the successful defendants their costs on the indemnity basis, rejecting arguments that their approach to mediation and alternative dispute resolution (ADR) should attract a costs penalty. Amongst its findings, the court held that it was reasonable for the defendants to decline to mediate an unfounded claim and that they should not have to entertain unrealistic conditions or contrived settlement dynamics.
What the case was about
The dispute concerned a valuable Chelsea property (including a lower ground floor flat) owned by the First Defendant, Janice Grijns. The claimant, Andrew Grijns, was Ms Grijns' son and had lived at the property for many years. A protracted feud developed regarding ownership of the property and promises which had allegedly been made to Mr Grijns regarding his interest in it.
In June 2023, Mr Grijns issued proceedings against his mother and brothers. Mr Grijns advanced a proprietary estoppel claim, claiming an entitlement to a substantial beneficial interest in the property (or, at least, an irrevocable license to occupy it) by virtue of assurances or promises allegedly made to him by his mother regarding the property, and his reliance on those assurances or promises to his detriment. He also advanced a claim in trespass, as a result of his mother and brothers having forcibly entered the property in June 2023 with the alleged intention of his removal from and sale of the property.
The court dismissed all of Mr Grijns' claims (Grijns v Grijns & Ors [2025] EWHC 1413 (Ch)). The court declared that Ms Grijns was sole legal and beneficial owner of the property, found that Mr Grijns had been a trespasser from 1 August 2023 (when Ms Grijns had counterclaimed for possession), and ordered him to pay mesne profits. The only limited point on which Mr Grijns succeeded was to narrow the period for his payment of an account of profits for the rental of the lower ground flat to a short window in 2023.
The judge emphasised that Ms Grijns and the other defendants had plainly "won the event". The starting point on costs was therefore that they should have their costs.
The costs fight
Mr Grijns argued for no order as to costs, despite losing on almost every point.
The court first refused to entertain Mr Grijn's argument for a reduction of 10% of the defendants' recoverable costs to reflect his "modest success" on the accounting issue. The court found that this was a peripheral point and not cost-significant.
It then went on to consider Mr Grijns' submissions regarding pre-action conduct and the defendants' approach to mediation and settlement. Mr Grijns' position was that:
- the defendants' conduct around the June 2023 incident merited a 50% costs penalty; and
- their attitude to mediation and settlement justified a 30–50% deduction.
The defendants' conduct in June 2023 was found to be lawful, not an attempt at "self-help" eviction, and in any event did not block a realistic settlement on the facts.
From there, the court decided that the sensible starting point was to first assess costs liability absent any potential penalty, then consider whether the defendants' conduct as to mediation or settlement should give rise to adjustment.
Indemnity costs
The judge held that Mr Grijns' claim was not just weak, it was outside the norm. The assurances alleged to have been given by Ms Grijns regarding the property were "constructed" and inconsistent with contemporaneous documents and conduct. The court viewed the litigation as a vehicle to extract a settlement and pointed to pressure tactics (raising the issue of capacity without following through and issuing a late committal application) consistent with this. This justified indemnity costs.
Settlement offers
The court then considered settlement offers. Mr Grijns made four offers between May 2023 and October 2024, the "best" of which would still have required payment to him of around £900,000 on a claim which he ultimately lost. The court held there was nothing unreasonable in refusing to treat those offers as a basis for negotiation, and that rejecting unrealistic offers does not justify a costs penalty.
The defendants had also made settlement offers, both during the proceedings and beforehand, which had not been accepted by Mr Grijns.
Mediation
The court then turned to mediation. Mr Grijns argued that the defendants unreasonably failed to engage in ADR and that there had been a consistent failure to respond to repeated requests.
The court noted that the defendants never refused a request to mediate. The judge reviewed the key authorities on ADR and costs, including Halsey v Milton Keynes General NHS Trust [2004] EWCA Civ 576 and PGF II SA v OMFS Co Limited [2013] EWCA Civ 1288, and the Jackson ADR Handbook, and noted that, "the starting point, where there has been a failure to respond to a serious request to mediate, is that the party failing to respond is normally to be regarded as having acted unreasonably".
However, he underlined two points from PGF II:
- this is a general rule and failing to respond is not automatically unreasonable; and
- even if there is an unreasonable failure to respond to a request to mediate, it would not automatically give rise to a costs penalty, but is a factor in the broader assessment of conduct when determining costs. The court noted that the Court of Appeal's approach in Gore v Naheed [2017] 3 Costs LR 509 supports this analysis.
The judge also noted that, as set out in PGF II, the fact that a party could reasonably have refused to mediate is not, in itself, an answer to an allegedly unreasonable failure to respond to a request to mediate. However, whether the defendants could have reasonably refused was relevant to the overall consideration of the approach they adopted and the question of whether any cost penalty should apply.
On the facts, the court concluded that there was "no doubt at all" that it would have been wholly reasonable for the defendants to refuse to mediate.
As set out in the ADR Handbook and Halsey, situations in which the courts have determined it to be reasonable for a party not to mediate include where parties face what they consider to be an unfounded claim (as the judge found this claim was) and where they wish to contest the claim rather than settle to buy it out (as was the case here).
In fact, the court noted that mediation was first raised by the defendants at an early stage, even though they would have had good reason not to do so with regard to the merits. The court found that any early progress towards mediation was frustrated by Mr Grijns' unreasonable insistence on excluding his brothers (despite the fact that they were defendants and despite their clear interest and roles, including powers of attorney) and by his refusal to provide targeted disclosure that the defendants had requested to facilitate realistic settlement discussions. By the time matters progressed through a tight trial timetable, there was no practical "space" to mediate before trial.
Against that background, the judge concluded that it would be "inaccurate and over simplistic" to characterise the defendants' approach to mediation as being unresponsive and was very far away from the "silent non-engagement" discussed in PGF II. The judge held there was no unreasonable non-engagement with ADR on the part of the defendants and no basis to penalise them on costs.
Where this sits after Churchill
Churchill v Merthyr Tydfil County Borough Council and others [2023] EWCA Civ 1416 confirmed the court's power to stay proceedings or order parties to engage in ADR. Amendments to the CPR (including CPR 1.4, 3.1 and 44 (on costs)) followed in October 2024, cementing the court's case management power to order ADR and consider ADR compliance and engagement when exercising its discretion on costs.
This judgment illustrates that while courts can compel ADR and will expect parties to engage with ADR, they won't punish a party for not entertaining unrealistic terms or declining to mediate a claim which is unfounded and where the opponent's conduct frustrates meaningful progress.
Learning points
Practical learning points which arise from issues in this case include:
- Treat ADR as part of case strategy from day one. Build in merits reviews and keep a record of your reasons for proposing, accepting or declining ADR.
- Do not ignore a serious ADR invitation. A prompt, reasoned written response setting out why mediation is inappropriate now (or what preconditions are needed to make it worthwhile) will help protect your position.
- You can reasonably refuse to mediate an obviously unfounded claim. Where the claim is weak and geared towards the extraction of a settlement, a refusal to mediate may be justified.
- Consider mediation preconditions. Insistence on excluding necessary parties or imposing artificial dynamics can justify refusal. Record why such terms make mediation unrealistic. Conversely, carefully consider requests made in order to facilitate ADR (such as limited disclosure).
For further discussion on this topic, please contact Duran Ross, Partner, Dispute Resolution.