13 07 2023 Insights Litigation & Dispute Resolution

S.1.391 25 years on - and the Harrington Undertaking

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Practice Corporate and Commercial Litigation

As S.I. 391/1998 - Rules of the Superior Courts (No 6) Disclosure of Reports and Statements approaches its 25th birthday. The decision of the Court of Appeal in O’Flynn v Health Service Executive [2022][i] of Mr. Justice Noonan provided a detailed overview of the case law since its introduction and showed some of the short comings of the regime, particularly in relation to more sophisticated defendants having regard to Harrington Undertakings. The Rules Committee of the Superior Courts were empowered to introduce S.I. 391 from Section 45 of the Courts and Courts Officers Act 1995.

Background Law- Disclosure of Expert report Reports and the Harrington Undertaking

The principles of S.I. 391/1998 are designed to forewarn a party of the expert evidence with which it may be confronted and has no role in investigating the strengths or weaknesses of an opponent’s case.[ii] It should facilitate the concept of a level playing field and possibility of the early resolution to proceedings. The purpose according to Judge Geoghegan in Kincaid V Aer Lingus Teo [2003] 2IR314, “is not to disclose the strengths and weaknesses of each other’s case but rather to prevent surprise evidence being thrown up at trial with which the other party, at that stage is unable to deal”. Any exchange should be simultaneous to avoid any danger that the rules can be abused to enable one party to gain an advantage over another.[iii] As Judge Noonan explained in O’Flynn, the purpose was to ensure “both sides went into trial with their cards face up on the table”.

According to Harrington v Cork County Council,[iv] the requirement of fairness is not voided by the non-existence of expert reports by a defendant. Where a party certifies that no expert report exists on its behalf to be furnished, the onus falls on the other party to furnish its expert reports. However, such disclosure may be conditional upon the receiving party providing an undertaking that the reports will not be given, directly or indirectly, to any expert retained by the receiving party until after such expert has furnished their own report.

O’Flynn v Health Service Executive [2022]

In the O’Flynn case, the Plaintiff sought damages for personal injuries arising from alleged medical negligence. The Appeal Court noted that the Plaintiffs case had been pleaded “in the most general and non-specific way”, that the Defendant had “for whatever reason” decided not to seek particulars of negligence but instead “it had not yet instructed experts until it sees the Plaintiff’s reports as it simply doesn’t know the case it has to meet”. The Plaintiff retained nine experts accordingly listed on its schedule pursuant to S.I. 391/1998. The defendant furnished its disclosure schedule but listed no experts and sought an exchange while offering a Harrington Undertaking. The Plaintiff refused and the defendant issued a motion to compel disclosure.

Unlike in Harrington, which was a personal injury action arising from an RTA where according to Judge Noonan in O’Flynn the “Plaintiff’s lawyers considered that sufficient protection would be afforded by the undertaking they proposed” in O’Flynn it was argued that Harrington Undertaking did not provide adequate protection as the defendant had its own internal experts who could consider the reports and therefore gain a litigation advantage even in the absence of obtaining further independent expert opinion.

High Court

Judge Cross refused the motion and suggested a modified form of Harrington Undertaking to the effect that the reports be disclosed only to the defendant’s legal team and not to the defendant itself.

Court of Appeal Decision

The Court of Appeal upheld the refusal of the motion but made a different order,

  1. Each party’s disclosure schedule should identify the experts it intends to call, their area of expertise and whether they have written a report or not;
  2. Reports should be exchanged on a simultaneous basis where possible;
  3. Where a party has not decided as to what experts upon which they intent to rely then exchange of reports should proceed on a like for like basis;
  4. If there is uncertainty as to what amounts to like for like reports, the parties may indicate in a general sense what issues the expert evidence seeks to address;
  5. If the defendant advises that it does not intend to call an expert to give evidence on an identified issue, the Plaintiff can furnish their expert reports on that particular issue, subject to a Harrington Undertaking;
  6. If on receipt of that Plaintiff report, the defendant changes its mind and decides to retain an expert to dispute that plaintiff expert evidence, then the defendant will need leave of the High Court that it is in the interests of justice to do so;
  7. Any application should be by way of notice of motion;
  8. (v), (vi) and (vii) will apply mutatis mutandis (making necessary alterations while not affecting the main point at issue) to the plaintiff;
  9. The parties remain free to withdraw any expert from their schedule.


This case turns on its own facts and Mr. Justice Noonan was clear to specify that it was not his intention that this should apply to every personal injury action or indeed every claim involving professional negligence. O’Flynn was “most unusual if not unique” in that no experts had even been retained by the Defendant and the court noted that in most clinical negligence claims the defence experts are known as at the time of proposed exchange and the defence list is “enhanced” when seeing the list of plaintiff’s experts when they become aware of areas of expertise of the plaintiff’s witnesses.

However, this judgment certainly indicates the courts willingness (and the necessity) to intervene in seeking to avoid any litigation advantage by blindsiding the other party at a late stage in proceedings and Judge Noonan also noted that “there were significant shortcomings in the disclosure regime introduced by S.I. 391 as this case shows” and suggested it would benefit from “recalibration”.

[i] O’Flynn v Health Service Executive [2022] IECA 83

[ii] Galvin v Murray [2001] 1 IR 331

[iii] Kincaid v Aer Lingus Teoranta [2003] 2 IR 314

[iv] Harrington v Cork County Council [2015] IEHC 41

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