Irish Supreme Court confirms witnesses must speak up about cartels or risk prosecution

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Philip Andrews
McCann FitzGerald, Dublin

Seán O’Dea
McCann FitzGerald, Dublin

Amy Ryan
McCann FitzGerald, Dublin


There has been a longstanding question over the constitutionality of the crime (under Irish law) of withholding from the Gardaí (Irish police), without reasonable excuse, any information which a person has about a criminal cartel and knows might materially assist in preventing, apprehending, prosecuting or convicting that cartel.  A recent decision of the Irish Supreme Court, on a similar crime of withholding information about a murder case, appears to clarify that it is in fact constitutional to ban staying silent about crimes.

On 28 May 2019, the Supreme Court delivered its judgment on the constitutionality of Section 9(1)(b) of the Offences Against the State (Amendment) Act 1998. Under this Section, it is an offence to withhold pertinent information relating to certain serious offences (eg, murder) from the Gardaí, without a reasonable excuse. 

The Supreme Court overruled the High Court, which had previously found the provision infringed the right to silence and was impermissibly vague. The Supreme Court reasoned that the right to silence is woven into the privilege against self-incrimination. It was noted that the Section is ‘expressly aimed at witnesses to crime or those who have information about a crime’ only. As the obligation applies only to non-participants, it expressly preserves the right to silence, the Court found. 

In a practical sense, this means that a witness is obliged to come forward if they have information relating to a serious crime that has been or is yet to be committed. Otherwise, that witness is guilty of an offence, whereas a participant does not have the same obligation.

For the purposes of competition law, this case clarifies the position of the law in what was previously a grey area. Cartels are criminalised in Ireland by Section 6 of the Competition Act 2002. The cartel offence is a ‘relevant offence’ under the Criminal Justice Act 2011, which includes an offence almost identical to the prohibition determined by the Supreme Court to be constitutional, consisting of withholding material information from the Gardaí in relation to any ‘relevant offence’. 

The case appears to clarify that, where a person is a participant/facilitator of a cartel, that person has the ‘reasonable excuse’ of avoiding self-incrimination. However, a person not party to a cartel, who is privy to information which they know or even believe to be material to a cartel prosecution and who does not tell the Gardaí, could face imprisonment up to a maximum of five years and/or a fine up to €5,000.