The dramatic move follows a probe by senior gardaí on foot of complaints in the Roma report, written by then Ombudsman for Children Emily Logan and published last July.
The arrest will raise issues in relation to the work of both gardaí and the media, the right to privacy of people and the strong powers brought in under the Garda Síochána Act 2005.
This act makes it a criminal offence for a garda to disclose information in certain circumstances, although it does provide some defences.
The Garda investigation was immediately ordered by then interim commissioner Nóirín O’Sullivan on foot of the report’s publication. The investigation team was headed by a chief superintendent and a detective superintendent, who interviewed gardaí and examined mobile phones.
Ms Logan was tasked by then justice minister Alan Shatter to investigate the Garda handling of the two blonde Roma children who were removed by gardaí from their families, one in Tallaght and the other in Athlone, on suspicion they had been abducted.
In her inquiry report, Ms Logan strongly criticised the release of information about ‘Child T’ — the seven-year-old Roma girl removed from her Tallaght home on October 21, 2013. She said “sensitive information” entered the public domain “inappropriately” in a newspaper article the following morning.
The report said this was “a very serious infringement of Child T’s privacy and also that of her family”. It said the level of information in the article was available only to the gardaí and the HSE.
Ms Logan said written reports prepared internally within An Garda Síochána and the HSE “may have acted as source material for an article published on the morning of 22 October”. She said there were no written HSE reports on October 21.
The report said: “The inquiry notes further that there were striking similarities between the text, form and content of the information found in the article published on the morning of 22 October and the only written report prepared within An Garda Síochána on 21 October.” It said the level of detail in the article and, in particular, the article’s “resemblance to the only written Garda report that existed on the evening of 21 October, 2013, leads the inquiry to believe on the balance of probabilities that the information in question came from someone within An Garda Síochána”.
“The inquiry believes that the release of details regarding Child T into the public domain may have been the result of a breach of discipline and/or an offence.”