Supreme Court: Appeal allowed in US military aircraft graffiti case

About this case:

• Citation:
  [2026] IESC 49
• Judgment:
  External link
• Court:
  Supreme Court
• Judge:
  Ms Justice Aileen Donnelly

Delivering judgment for the Supreme Court, Ms Justice Aileen Donnelly confirmed that “Where the DPP cannot establish an ingredient of the offence of criminal damage – that it was committed without lawful excuse – the DPP cannot establish that the offence of criminal trespass was committed when the allegation is that the trespass was carried out with the intent to commit that criminal damage.”

Background

In April 2017, the appellant and a co-accused entered a high-security restricted area at Shannon Airport, inter alia damaging a US military aircraft with graffiti consisting of writing “Danger, danger, do not fly” and drawing a “U” shape in marker on the aircraft.

The appellant and his co-accused were charged with criminal damage and trespass giving rise to a reasonable inference that they intended to commit an offence or to damage property. 

While the appellant had not given evidence at trial in the Dublin Circuit Criminal Court, his co-accused advanced his personal belief that his actions were justified as a means of preventing the death of persons in the Middle East at the hands of US Military personnel, and that both men had acted with that common purpose.

The trial judge charged the jury in respect of the defence of “lawful excuse” in respect of the criminal damage by reciting s.6 of the Criminal Damage Act 1991, but did not charge the jury in respect of lawful excuse or the related common law defence of “necessity” as a defence to the criminal trespass charge.

The men were ultimately found guilty only on the count of trespass contrary to s.11 of the Criminal Justice (Public Order) Act 1994, and were acquitted of the criminal damage charge.

The appellant appealed against his conviction on grounds that the trial judge, in her charge to the jury, had failed to direct the jury on the defence of necessity in relation to the trespass offence.

His appeal having been dismissed by the Court of Appeal, the appellant was granted leave to appeal to the Supreme Court on the defence of necessity, its application in relation to the trespass charge and how it might relate to the actus reus and mens rea for the offence of trespass on the facts of the case.

The Supreme Court also considered that the parties should address the ingredients of the offence of criminal damage pursuant to s.6 of the 1991 Act, and particularly whether the existence of a lawful excuse for the criminal damage would also be relevant to the offence of criminal trespass where it is alleged that the trespass occurred with intent to commit criminal damage.

The Supreme Court

Having considered the relevant legislation and caselaw and the parties’ submissions, Ms Justice Donnelly explained that the proper interpretation of s.11(1) of the 1994 Act is that the offence can only be committed where it is reasonable to infer from the circumstances of the entry, that such trespass was with intent to commit an offence or to unlawfully interfere with property.

Accordingly, if an accused establishes that they did not have the intention required by the statute, then the trier of fact could not be satisfied that the offence had been established and it would be unreasonable to draw an inference of guilty intent.

The judge noted that, in making “unlawful interference” with property an ingredient of the offence, the legislature’s intention was that something more than mere trespass must be established and that the section requires, at a minimum, an intention to have an effect on the use or enjoyment of property.

Noting that it was clear from the indictment that the DPP’s allegation was that the trespass occurred with the intent to commit criminal damage, Ms Justice Donnelly observed, “Where the DPP cannot establish an ingredient of the offence of criminal damage – that it was committed without lawful excuse – the DPP cannot establish that the offence of criminal trespass was committed when the allegation is that the trespass was carried out with the intent to commit that criminal damage.”

The judge continued, “In those circumstances, the existence of a lawful excuse for any acts of damage means that the prosecution could not satisfy the jury that the accused had entered as a trespasser in circumstances giving rise to the reasonable inference that he intended to commit criminal damage.”

The Court considered that usually, a failure to charge on such a vital ingredient of the offence would be a fundamental error which would justify quashing the conviction.

The Court had regard to the specific factors in the appeal, including the interlinking of the two charges both in the drafting of the indictment and in the manner in which the trial was run, the trial judge’s inadequate charge to the jury, that the Court could only speculate as to why the jury acquitted the men on the criminal damage charge, and the possibility that a dismissal of the appeal would cast doubt on the acquittal of the criminal damage charge.

In the circumstances where a fundamental error of law occurred, the Supreme Court allowed the appeal and having regard to the minor nature of the offence, determined that the public interest would not be served by a re-trial.

Noting that the defence of necessity had not been raised at the trial, the Court then turned to consider the defence of lawful excuse in the context of criminal damage offences.

Highlighting that “without lawful excuse” is an ingredient of the offence of criminal damage, the Court was satisfied that whether or not damage was committed “without lawful excuse” is to be decided on consideration of the evidence as a whole and if it has been demonstrated by the prosecution on the available evidence that no lawful excuse arises, the defence must adduce evidence of a lawful excuse if they wish to have that issue considered.

Ms Justice Donnelly explained that whether an excuse amounts to a lawful one is a mixed question of law and fact, with the test for whether a person has a lawful excuse under s.6 of the 1991 Act having subjective and objective elements.

Noting that there are limits on when a “lawful excuse” may arise, the Court set out that a trial judge is entitled to take the issue of “lawful excuse” from the jury “where there is no evidence that, even in the circumstances as the accused believes them to be, the act or acts alleged to constitute the offence could possibly protect a person or property.”

Recognising that this will be the position when there is no causal nexus between the alleged act and the purpose for which it is executed, including circumstances where the intended purpose is remote and depends on highly speculative acts by one or more persons over which the defendant has no control, the Supreme Court considered that in the case before it, the honest belief that the act of defacing an airplane in this jurisdiction would prevent the killing of persons in the Middle East was so far remote such that it was not possible to discern a causal connection.

Conclusion

Accordingly the Supreme Court allowed the appeal and directed that there be no retrial.

The People (at the suit of the Director of Public Prosecutions) v Dowling [2026] IESC 49