Doyle v Houston: Elevating the Threshold for “Legal-Practitioner-and-Client” Costs in Cases of Procedural Abuse

Introduction

The High Court decision of Mr Justice Kennedy in Doyle v Houston ([2025] IEHC 391) concerns the costs consequent upon an interlocutory injunction restraining the defendant’s trespass. Although the injunction itself had already been granted in an earlier judgment ([2025] IEHC 373), the present ruling lays down an important costs principle: where a party’s conduct is persistently obstructive, abusive or vexatious, the court may—indeed should—award costs on the more punitive “legal practitioner and client” basis rather than the ordinary “party and party” basis.

The plaintiff, Ms Wendy Doyle, sought enhanced costs after successfully obtaining the injunction. The defendant, Ms Eugenie Houston (a barrister acting for herself), opposed that application and continued to press a welter of collateral allegations against the plaintiff, her solicitors, and the judiciary.

Summary of the Judgment

• Entitlement to costs: As the successful party, the plaintiff was prima facie entitled to her costs under section 169 of the Legal Services Regulation Act 2015 (LSRA) and Order 99 of the Rules of the Superior Courts (RSC).
• Basis of assessment: Applying Order 99 r.10(3) RSC and the principles in Trafalgar Developments v Mazepin, the Court held that legal-practitioner-and-client (solicitor-and-client) costs were warranted because of the defendant’s:
  • “extraordinarily obstructive approach”,
  • persistent failure to comply with directions,
  • re-litigation of resolved issues, and
  • gratuitous ad hominem attacks on the plaintiff and her lawyers.
• Quantum of costs: The Court declined to measure the costs immediately, leaving the figure to be adjudicated “in default of agreement” after any appeals.

Analysis

1. Precedents Cited

Justice Kennedy built upon a trilogy of authorities that sanction punitive cost orders:

• Geaney v Elan Corporation plc [2005] IEHC 111 – Kelly J used solicitor-client costs to signal disapproval of discovery misconduct.
• Dunnes Stores v An Bord Pleanála [2016] IEHC 697 – Barrett J deployed the same scale where proceedings were “infected by abuse of process”.
• Trafalgar Developments Ltd v Mazepin [2020] IEHC 13 – Barniville J (as he then was) synthesised the principles, later endorsed by the Court of Appeal in Bank of Ireland v Balford Construction [2023] IECA 26.

The Court also referenced:

• Section 168–169 LSRA 2015 (statutory entitlement and discretion on costs);
• Order 99 RSC (general costs framework);
• Riordan v An Taoiseach [2001] 4 IR 463 (criteria for vexatious litigation); and
• the defendant’s prior “Isaac Wunder” history—multiple higher-court rulings warning of vexatious conduct.

2. Legal Reasoning

Justice Kennedy followed the structured approach mandated by Trafalgar:

1. Identify the conduct. The Court catalogued a long pattern of behaviour: obstruction, delay, repeated non-compliance, and personal attacks devoid of evidential basis.
2. Examine explanations. The defendant offered none that could justify or mitigate the conduct.
3. Assess consequences. The plaintiff incurred “unexpected, unnecessary and unnatural” effort and expense, and the Court’s own time was consumed.
4. Determine appropriateness. Given seriousness and repetition, solicitor-client costs were “necessary to mark the Court’s displeasure”.

Importantly, the Judge emphasised the deterrence function of such orders, especially where litigants weaponise court processes to harass opponents or malign lawyers under the cloak of privilege.

3. Impact of the Decision

• Clarifies threshold for solicitor-client costs in Ireland: not limited to discovery abuses or fraud allegations but extends to persistent procedural harassment and ad hominem attacks.
• Reinforces judicial control over repeat or vexatious litigants, complementing Isaac-Wunder orders.
• Guidance for practitioners: Advises solicitors and counsel that seeking elevated costs is viable where a party’s conduct amplifies costs beyond the ordinary run of litigation.
• Potential ripple effect: Future interlocutory (and even substantive) hearings may see more applications for solicitor-client costs where obstruction is evident, leading to swifter case management and reduced abuse.

Complex Concepts Simplified

• Party & Party Costs – the standard scale; the successful party recovers only costs necessarily and reasonably incurred for prosecuting/defending the claim.
• Legal-Practitioner-and-Client (Solicitor-Client) Costs – a higher scale; all costs the solicitor can reasonably charge the client are recoverable, including items that might be excluded on the party-and-party basis. It is punitive/deterrent in nature.
• Interlocutory Injunction – a temporary court order granted before trial to preserve the status quo (here, restraining trespass) until determination of the substantive rights.
• Isaac Wunder Order – an order restricting a vexatious litigant from instituting proceedings without leave of the court.
• Fi Fa – a writ of fieri facias enabling the Sheriff to seize property to satisfy a judgment debt.
• Stay of Execution – suspension of a judgment’s enforceability pending appeal.

Conclusion

Doyle v Houston underscores the judiciary’s readiness to deploy “legal-practitioner-and-client” costs as a corrective and deterrent tool where litigants: (i) flout procedural directions, (ii) recycle settled grievances, (iii) launch unsubstantiated personal attacks, and (iv) inflate the other side’s costs.

Key takeaways include:

• Solicitor-client costs are no longer confined to discovery abuse or fraud accusations; they will apply to any pattern of conduct that the court views as an abuse of its processes and a waste of resources.
• Courts will scrutinise both the nature and the consequences of misconduct; the greater the prejudice and delay, the more likely punitive costs will follow.
• Litigants in person— even legally qualified ones—are not exempt; familiarity with legal process may amplify culpability.
• While elevated costs punish misconduct, the quantum will generally be left to the adjudication office unless special circumstances justify immediate measurement.

In the broader legal landscape, the ruling fortifies the message that “the right of access to the courts does not entail a license to abuse those courts or malign one’s opponents under privilege.” Expect future Irish litigation to cite Doyle v Houston whenever heightened costs are sought to curb procedural excess.