When Minister for Justice Jim O’Callaghan initially told the news media that the Army would be deployed to remove vehicles obstructing roads and blocking ports as part of the protest against fuel prices, reactions among senior gardaí and Defence Forces personnel ranged from concern to confusion.

There was surprise and disbelief that a Minister for Justice could apparently be unaware of the sensitive, not to say dangerous, boundary that he was crossing, casting aside the protocols of more than a century since the establishment of An Garda Síochána and Óglaigh na hÉireann.

In fairness, what he said was the Army would “remove the vehicles”, without referring to the protesters. But in the circumstances it was a distinction without a difference. Protest organisers described it as a provocation and a threat. A more felicitous statement later sought to regain lost ground but he had given those orchestrating the disruption the stick they needed with which to beat Government.

Minister Helen McEntee, holding the Defence portfolio, seemed nonplussed by O’Callaghan’s announcement. Her annoyance was clear in her declining to confirm she had been consulted, adding delicately that processes at senior Government level could be “improved”.

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It would appear that while there had been contact between the Department of Justice and Garda Headquarters before O’Callaghan spoke, no plans had been confirmed between the Garda Depot and the Defence Forces. When this occurs, it is known as the “C70” process.

Protocols between the Garda and the Defence Forces go back to the foundation of the State and are grounded both in common law and in statute (Defence Act 1954). They reflect the distinction between civil and military authority and the prerogatives of each within their separate spheres. Gardaí are civilians, subject to civil law. Soldiers operate under military law and are answerable for their actions to military courts.

During the Civil War, responsibility for public safety was largely in the hands of the National Army. But thereafter, government pushed rapidly to get the soldiers back into barracks, replacing them with unarmed police. That process was completed by 1924 and was followed by large-scale Army demobilisation.

Ministers down the decades have scrupulously observed the distinction between civil policing and the military function, with Bunreacht na hÉireann placing the president in “supreme command” of the Defence Forces. Defence ministers have not purported to speak for the gardaí. Justice ministers have never implied they have any role relating to the military or what they do.

Under the Defence Act, the gardaí may request the military to act as an “aid to the Civil Power”. This will occur, for example, when there is a requirement for bomb disposal skills. And it was routine for armed soldiers to accompany gardaí on Border patrol or guarding banks during the Troubles. But primacy rests with the gardaí. In such operations, a garda at basic grade stands above any Army officer and can take orders only from his or her garda superiors.

Soldiers do not have the powers of gardaí, including the power of arrest. This, and the fact they have not been trained in police techniques, are the principal reasons they have never been deployed by the State in any control situation involving the public. And this is the reason O’Callaghan’s announcement was so alarming. The idea of soldiers going head-to-head against protesters would be abhorrent. Even in critical circumstances such as the destruction of the British embassy in 1972 or in various prison riots, the State has never sent its military in to confront the citizenry.

In the event, no soldiers were deployed beyond the drivers who operated heavy-lifting transporters at the fuel depots. The Minister’s language the next day was more considered. Gardaí, he said, were preparing for deployment and if necessary, the Defence Forces would be there in support. Strictly speaking, that would not be his call either, but an operational matter for gardaí themselves.

Blurring the lines between police and military operations, and between police and military personnel, is a common occurrence where democratic norms are diluted or suppressed. Peron did it in Argentina. Franco did it in Spain. Duvalier did it in Haiti. Certain modern African states do it. Trump has sought to do it, deploying the National Guard in a policing role in Washington. Significantly, in spite of months of bitter confrontation between British miners and police in 1984-1985, Margaret Thatcher never sought to send soldiers against the strikers. Westminster governments knew the catastrophic consequences of deploying the military on the streets in Northern Ireland.

Something of an unfortunate precedent was arguably set here in 2011 when Alan Shatter was assigned the dual role of minister for justice and minister for defence. It disquieted civil servants, senior gardaí and military who were concerned at the idea of all security authority as well as intelligence – criminal, subversive and military – going back to one minister. Garda Security and Intelligence – as far back as the old “C3” structures and Defence Forces Intelligence, formerly “J2” – have always kept an eye on each other, while preserving their own independence and prerogatives.

Co-operation and pooling information are essential. But maintaining a watchful coexistence between the depot and defence headquarters was always considered a safety check. It proved to be necessary more than once. In 1970, during the arms crisis, gardaí had to act against members of Defence Forces Intelligence. A few years later, Defence Forces Intelligence played a role in the unmasking of MI5 agents in the Garda Depot.

The balance between our civil and military institutions is a delicate one, tried and tested over more than a century and contoured to preserve the values upon which independent Ireland was founded. Those engaged in public conversation that touches upon it, especially those in high office, need to be ultra-careful in choosing their words.

Conor Brady is author of two political histories on An Garda Síochána and a former editor of The Irish Times

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