The High Court has ruled the State has a constitutional duty to make "reasonable efforts" to assign a bilingual judge in a District Court criminal trial as requested by a man who wants to conduct his side of the case in Irish.

Ms Justice Una Ní Raifeartaigh made what she described as the "novel" finding in favour of a Cork County Councillor, aged in his 50s, of Ballintemple, Cork, who is charged with blacking out street names in Cork called after Queen Victoria.

Diarmaid Ó Cadhla's District Court case remains on hold pending his High Court proceedings, brought after District Judge Olann Kelleher said he was entitled to hear the case through an interpreter.

They held the duty of the State arises under Article 8 of the Constitution, which states: "The Irish language as the national language is the first official language".

While her identification of the constitutional duty under Article 8 is "novel", she believed the practical effect would be "very limited" because the State's practice to date has been to assign a bilingual judge in most of the very small number of cases where the issue has arisen over the years.

Opposing his action, the State argued any "disadvantage" to a person who wished to conduct their side of a case in Irish could be "cured" by the process of interpretation/translation and disputed it had any duty under Article 8 as argued for.

In her judgment published this week, Ms Justice Ní Raifeartaigh stressed this was a "language rights", rather than due process case.

It was about the right to present a case in Irish and to be heard and understood in Irish by the District Judge dealing with the case. It was not about "forcing" an all-Irish trial on the other side but to have a bilingual judge preside over a bilingual trial.

The net question is whether the State has a duty of any kind under Article 8 to provide a bilingual District Court judge when an accused person has chosen to exercise their "now well-established" constitutional right to present his side of the case in the Irish language.

The net issue relates only to the particular case of an accused facing a criminal trial in the District Court and is not intended to be of any wider application, she said.

Having examined the legal authorities, she concluded the State has a duty under Article 8 either to make reasonable efforts to assign a bilingual District Court or to assign such a judge "as far as is reasonably practicable".

Earlier, she noted this was the latest of several cases where a person accused of a criminal offence seeks to assert rights in connection with the Irish language.

The jurisprudence to date "emphatically" upholds the need for a "practical implementation" of the status of the Irish language as the first official language, she said.

She referred to "a historically lukewarm State commitment to the giving of practical support and resources to support the language in the administration of justice".

Ireland, she said, has a "peculiar and complex" relationship with the Irish language, with some people passionate about it, some indifferent and some hostile. The Irish speaking minority sometimes faces "surprising intolerance" towards its rights "from quarters usually more respectful of minority rights".

The legal theory is "very different" with the Constitution designating Irish as the first official language and "not merely one of two official languages", she said. This could not be regarded as "a quaint and aspirational relic of the thinking and culture of 1937" as Ireland recently took active steps to elevate the status of the Irish language within the EU.

While her identification of the constitutional duty under Article 8 is "novel", she believed the practical effect would be "very limited" because the State's practice to date has been to assign a bilingual judge in most of the very small number of cases where the issue has arisen over the years.

Her decision merely concluded this practice "is underpinned by a constitutional duty on the part of the State" and does not imply any further rights or duties in relation to other types of criminal trial, legal proceedings or non-legal proceedings. She considered the Official Language Act 2003 does not confer any legislative right regarding assignment of a bilingual judge and the issue arose "firmly in terms of constitutional right or duty under Article 8".

Her decision does not propose "in any fundamental way" to impact on selection or assignment of judges, she also said.

While the number of judges able to conduct a case in Irish appears to be "steadily decreasing", there is an "unofficial stream of goodwill", at least among some parts of the judiciary, which ensures that cases, including superior court cases, are heard in Irish and by Irish speaking judges on a "reasonably frequent" basis.

She observed that litigants seeking to have their cases heard in Irish are often viewed as being "obstructive or insincere" with many people automatically assuming, because they can also speak English, they do not really "need" to have the case heard, or part heard, in Irish.

The matter has been adjourned to later this month for making of formal declarations.