Disputes - Important Supreme Court Decision on Scope of Discovery

How should the courts respond to the difficulties posed by what might sometimes be considered to be the disproportionate burden imposed on the parties to litigation by discovery obligations?

This was the issue for the court in Tobin v Minister for Defence.1 In that case, the plaintiff was employed by the defendant as an aircraft mechanic in the Air Corps. The plaintiff alleged that during his employment he was exposed to dangerous chemicals and that as a result he suffered personal injury. The defence put the plaintiff on full proof of all facts except as to his employment with the defendant.

Discovery request

The plaintiff sought discovery of 15 categories of documents. The defendant objected to the burden of the requested discovery which it was estimated would take approximately two hundred and twenty man-hours to complete.

One category related to details of the chemicals to which the plaintiff was exposed. The defendant argued that the information required should be sought by way of interrogatories. The plaintiff replied that he did not have sufficient knowledge of the relevant chemicals to enable him to frame such interrogatories so their use would not allow for a fair disposal of the case.

High Court

The plaintiff was largely successful in the High Court. The court held that the discovery was necessary for and relevant to the fair disposal of his claim, notwithstanding the significant degree of work required to comply with it. McDermott J agreed with the plaintiff that the use of interrogatories would not suffice here. He also said that it was “noteworthy” that the defendant had made no admission that it exposed the plaintiff to dangerous chemicals.

Court of Appeal 

The Court of Appeal allowed in part the defendant’s appeal against the discovery order. Hogan J said that in light of the concerns regarding the burdensome nature of current discovery practice, the courts should seek out and contemplate alternative solutions. The principle that discovery should be refused where the information sought was otherwise available, by means of interrogatories or a notice to admit facts, was “fundamental”. Therefore, where discovery was likely to be extensive, no such order should be made unless all other avenues were exhausted and had been shown to be inadequate.

He said that the plaintiff should first seek the required information by means of interrogatories. He could renew his discovery application if the information obtained was insufficient.

Supreme Court

However, the Supreme Court took a different view allowing the appeal and largely restoring the order of the High Court.

Clarke CJ emphasised the importance of discovery that it “improves the chances of the court being able to get at the truth in cases where facts are contested. In that way, it makes a significant contribution to the administration of justice.” However, he also acknowledged that discovery can hinder access to justice if it becomes disproportionately burdensome.

Clarke CJ summarised the current position saying that a court:

“…will only order a party to make discovery if it is satisfied that the documents sought are both relevant and necessary for the fair disposal of the case or to save costs. In addition, in an effort to limit the burdens, costs and delays incurred by orders for discovery in modern practice, two further considerations have sometimes been proposed; one being that of proportionality and the other being the suggestion that alternative, more efficient methods of disclosure should first be pursued.”

However, he said that the key criteria remained those of relevance and of necessity. The default position was that a document whose relevance had been established should be considered to be one whose production was necessary.

However, that default position could be displaced. If it could be shown that discovery would be particularly burdensome, then a court would have to consider a range of factors in deciding whether discovery was truly “necessary”. These included:

  • the burden which compliance would be likely to place on the party making the discovery; 
  • the extent to which it might reasonably be expected that the documentation concerned would play a reasonably important role in the proper resolution of the proceedings; and 
  • the extent to which there might be other means of achieving the same end but at a much reduced cost.

He also noted that confidentiality (as opposed to privilege) would not provide a legitimate basis for refusing to require disclosure of documents should they prove necessary to the proper administration of justice. However, it would permit the court to adopt appropriate measures to respect the importance of confidentiality by ensuring that it was only displaced when the production of confidential documentation proved truly necessary to the just resolution of proceedings.

Clarke CJ said that where it was suggested that the discovery of relevant documents was not necessary, the burden lay on the requested party to put forward reasons as to why this was so and at least initially, to suggest any alternative means of obtaining the relevant information which was less burdensome but potentially equally effective. A requesting party did not have to establish that they had exhausted all other procedures available to establish relevant facts before discovery could be sought.

The Importance of the Pleadings

Clarke CJ said that relevance should be determined by reference to the pleadings. Plaintiffs had to accept that if their pleadings were very wide, they were exposing themselves to wider discovery. The same could be said of defendants who put everything in issue.

A court could take into account the manner in which the case was pleaded, not only for the purposes of determining relevance, but also to assess the extent to which a party who objected to making discovery, on the grounds that it was excessively burdensome, had contributed to that situation by the manner in which they had pleaded their case.

Application of the Principles to the Facts of the Case

Clarke CJ said that here the issues surrounding exposure to particular chemicals were central to the plaintiff’s case and he was entitled to use procedural measures to ascertain the relevant information. The discovery burden on the defendant was “moderate” only.

He also emphasised that the defendant had put the plaintiff on proof of his entire claim. If it knew the answers to the proposed interrogatories, it was hard to see why appropriate admissions could not have been made already.

However, if it did not already have this information, then to give meaningful answers to these interrogatories it would have to do a significant amount of research. There was unlikely to be a significant saving of resources in adopting this approach instead of ordering discovery.


This is a significant decision of the Supreme Court emphasising the importance of discovery in the administration of justice in Ireland. However, it also acknowledges the burden the discovery in the modern era may impose on litigants and suggests a practical approach for parties both in their approach to pleadings and in navigating their way through the discovery process.

Our experienced Project Services team or your usual contact at McCann FitzGerald would be pleased to provide further information on this case or the discovery process generally.

  1. [2019] IESC 57.

This document has been prepared by McCann FitzGerald LLP for general guidance only and should not be regarded as a substitute for professional advice. Such advice should always be taken before acting on any of the matters discussed.