Mahon Tribunal v Keena & anor

Factual and Procedural Background

A Tribunal of Inquiry investigating certain planning matters issued a confidential letter to a prospective witness. The contents of that letter were leaked and published in The Newspaper in an article written by the first-named Appellant; the second-named Appellant was the editor. A copy of the letter had been sent to the first-named Appellant anonymously.

When the Tribunal sought to identify the source of the leak, it issued an order on 25 September 2006 compelling the Appellants to produce the letter and attend for questioning. Acting on legal advice and with the express purpose of protecting journalistic sources, both Appellants deliberately destroyed all copies of the document.

The Tribunal obtained an order from the High Court on 9 November 2007 compelling compliance. The High Court characterised the destruction of the document as “an outstanding and flagrant disregard of the rule of law” and ordered the Appellants to comply. On 31 July 2009, the Supreme Court allowed the Appellants’ substantive appeal, holding that the High Court had failed to strike the correct balance between journalistic privilege and the Tribunal’s interest.

Following their success on the substantive appeal, the Appellants applied for their costs in both courts. The Tribunal opposed and sought its own costs. The present ruling, delivered on 26 November 2009, addresses that costs application.

Legal Issues Presented

1. Whether, under Order 99 of the Rules of the Superior Courts, costs should “follow the event,” entitling the successful Appellants to their costs despite their conduct.
2. Whether the Supreme Court has discretion, in exceptional circumstances, to order a successful party to pay the costs of the unsuccessful party.
3. Whether the Appellants’ deliberate destruction of evidence justified an exercise of that discretion against them.

Arguments of the Parties

Appellants’ Arguments

• Invoked Order 99, rule 1(3) of the Rules of the Superior Courts, emphasising the general principle that costs should follow the event.
• Contended that, having succeeded on the substantive appeal, they were entitled to recover their costs in both the High Court and Supreme Court.

Plaintiffs/Respondents’ Arguments

• Sought an order that the Appellants pay the costs of both courts.
• Relied on the Appellants’ calculated destruction of crucial evidence, arguing that such conduct disentitled them to any costs award.

Table of Precedents Cited

Court's Reasoning and Analysis

The Court reaffirmed that, although Order 99 normally directs that costs follow the event, it retains a wide discretion to depart from that rule in exceptional circumstances. Citing Dunne v Minister for the Environment, it noted that no fixed principle compels an award of costs to a successful litigant.

The Court analysed the causal connection between the Appellants’ deliberate destruction of evidence and the inability of both the Tribunal and the courts to conduct a meaningful inquiry. That conduct was described as “reprehensible,” “calculated,” and “designed to subvert the rule of law.” The destruction directly shaped the course of the proceedings and led to the outcome in which the Appellants ultimately prevailed.

Because the Appellants’ own misconduct engineered the circumstances that underlay their legal success, the Court found it appropriate to exercise its exceptional discretion to deny them costs and instead award costs to the Plaintiffs/Respondents.

Holding and Implications

ORDER: The Plaintiffs/Respondents are entitled to recover the costs of both the High Court and the Supreme Court from the Appellants.

Implications: The ruling underscores the Supreme Court’s willingness to depart from the “costs follow the event” principle where a successful party has engaged in conduct that undermines the administration of justice. While creating no new formal precedent, it signals that deliberate destruction of evidence may justify exceptional costs orders against even successful litigants.