With the debate about ‘Brexit’ heating up in the final week before the Referendum, there has been more and more debate about what would happen to the border between Northern Ireland and the Republic of Ireland. During the conflict in Northern Ireland, the British, Northern Irish and Irish authorities were also concerned about this border, and how travel across it would be monitored. The British were most concerned about potential terrorists crossing the border from the Republic into Northern Ireland and Northern Irish terror suspects fleeing to the South. Throughout the 1970s, the British, as well as their local counterparts, attempted a series of different tactics to prevent border crossings, starting with an explicitly militarised approach to the experimentation with a more traditional immigration control system. As Vicki Conway wrote, it was not until the Anglo-Irish Agreements in the mid-1980s that the Irish border was effectively controlled from both the British and Irish sides.

Since partition in the 1920s, the border between Northern Ireland and the Irish Free State (the Republic of Ireland after 1949) had been porous, with relatively free movement on both sides of the border. Before the outbreak of the conflict in August 1969, the only republican activity seen across the border area in the post-war era was the short-lived ‘border campaigns’ of the Irish Republican Army in the late 1950s and early 1960s. Soon after it began, the border area became a focal point of the conflict – for the movement of republican fighters between the North and the South, and for attacks by Republicans upon the British Army and Royal Ulster Constabulary patrols situated at the border. A 1971 report outlined the problem as such:

The security problem in Northern Ireland is influenced by the relative ease with which men with subversive intent, with or without arms, ammunition or explosives, can enter Northern Ireland; and wanted men can escape. The movement occurs over the land border with Eire; though normal sea and air points of entry into Northern Ireland; and by illegal movement by sea and air.[1]

In August 1970, a car bomb killed two RUC members at Crossmaglen, which resulted in a partial closure of the border, blocking ‘unapproved roads in South Armagh, Castlederg Salient and Londonderry [sic[ Salient’.[2] According to a 1971 report on the border closure, 51 roads were closed, using spikes, but over the next two months, there were 83 recorded incidents of the blocks being removed from 29 different roads.[3] The report found that:

Resistance to the blocks was so determined and the result so ineffective that it was decided to abandon the operation. Spikes and other blocks were gradually removed during the period Oct – Dec 1970, and the sites tidied up.

As the violence in Northern Ireland increased over the next few years, various sections of the British and Northern Irish authorities attempted to devise ways of preventing Republican fighters from crossing the border, or from attacking border patrols inside Northern Ireland. The British Army attempted to transform the border into a militarised checkpoint, relying on a combination of blocking off ‘unapproved’ roads and vehicle/personnel checks at others. Central to this was an emphasis on vehicle and identification checks. However there were several problems that the Army and the RUC encountered when trying to enforce this policy.

Firstly, they found that there was too much border to guard at one time. A 1973 Home Office report stated:

There are 303 miles of the border. There are 20 approved roads, 187 approved roads and 17 concession routes… The facilities for crossing the border are much greater than the number of cross-border roads. In particular there are 30 miles of water, numerous lanes and smugglers’ pads and border lands which are easily negotiable on foot.[4]

The Northern Ireland Office found that if the entire border was to be guarded, the burden would fall to the RUC and proposed ‘strict control along a limited sector only’, based on where the border was most likely to be traversed by ‘subversive’ elements.[5] Stormont’s Government Security Unit proposed in March 1972 that there were two solutions patrolling the entire border. The first option was a ‘sealing’ of the border, while the second was a partial prevention of entry, particularly along ‘unapproved’ roads.

‘Sealing’ the border was seen as the ‘nuclear’ option as it entailed converting the entire border into ‘a militarized frontier, with a continuous glacis, minefield or other impenetrable barrier under constant surveillance’.[6] ‘The only points of entry’, the Unit then proposed, ‘would then be by the way of the 20 approved crossings, with 100% checks on all persons, vehicles and loads’.[7] This was an extreme option and the Unit warned:

It may be necessary to bring home to members of Parliament and the public what the ‘sealing’ of the Border really implies. Any measures on the lines of those described would be enormously costly in time, money and manpower; they would involve a dislocation of all legitimate cross-Border activities; they would have to be supported by a defensive blockade of the entire coastline; and their political and economic implications would be entirely unacceptable within the context of [the] EEC.[8]

More favourable was the partial prevention of entry, which would mean the blocking of some more difficult to police roads and the interception of vehicles on the remaining roads. However this still presented problems, with the Unit stating that any road closures would need to be weighed against ‘the hardship likely to be caused, the resistance to be encountered and the tying down of manpower to ensure that closures remain effective.’[9] The Unit warned that partial closures still required a large amount of manpower to guard both the closed and open routes. Furthermore, it was warned that ‘[p]ermanent check-points at vehicle crossings [would] also present shop window targets’ for attacks by Republican fighters.[10]

With the focus on intercepting vehicles crossing the border and the use of checkpoints, there was also disagreement over how these interceptions would function. At first, there was a push for compulsory ID checks on all of those who crossed the border, but it was acknowledged that this was ‘a valuable aid to the identification of drivers, but that this did not help in relation to passengers’,[11] as non-drivers in both the UK and the Republic of Ireland were not required to hold identification papers at all times. Adding to this was confusion amongst the different agencies over whether Republic of Ireland driver’s licenses had photographs or not.[12]

A proposed alternative to the checking of driver’s licenses was the checking of vehicle registration papers. However it was deemed that this raised too many obstacles, particularly as numerous vehicles crossing the border (delivery trucks, hire cars, etc) would not necessarily have these registration papers in the vehicle. Furthermore, it was mentioned that there was ‘a well-founded objection to keeping registration books in cars because both can be stolen together.’[13]

To get around these specific problems, it was floated whether all people living or working within a designated border zone could be issued with a special vehicle permit.[14] In the same document, it was suggested ‘if there is a case on security grounds for imposing this requirement, it should be applied over the whole province and not only in a specified border area.’[15] However with both suggestions, it was felt that this would be an onerous requirement and that permits could not quickly issued. The conclusion to these proposed checks was that ‘[t]he imposition of a requirement to carry vehicle documents would not necessarily bring about any substantial improvement in border security’ and that ‘[e]nforcement would present considerable difficulties’.[16]

Alongside the push for a greater insistence on documentation for those crossing the border, the Army also pushed for greater powers of search and seizure of suspected vehicles. As a 1973 Home Office document stated, ‘’[t]he army would like a clear power to seize vehicles so that they could be removed for close scrutiny’, and called for an expansion of the Special Powers Act 1922 to cover this demand.[17] While the requirements for compulsory carriage of documents were not followed through, greater powers of search and seizure were incorporated into the Northern Ireland (Emergency Provisions) Act 1973.

After much deliberation, it was debated whether the intense scrutiny placed upon cross-border travelling had brought many tangible benefits, particularly considering the amount of manpower involved. For example, one report stated:

In the first four months of 1971, over 200,000 cars have been searched in Northern Ireland and in only about 10 have wanted men, arms or explosives been found; some 25 or more evaded road checks.[18]

However the report also qualified that there were some gains to this approach, adding:

Nevertheless the security dividend from a tighter control of the border area must not be underestimated: a reduction in cross-border explosive attacks and the interception of wanted or wounded men escaping from Belfast are typical potential gains. (My emphasis)

After 1972 (the deadliest year in the 30 year conflict), the Provisional IRA shifted tactics to attacking targets on the British mainland, while Loyalists targeted civilians in the Republic of Ireland. Although there were two bombings at the Old Bailey in 1972, it was not until the following year that the British mainland campaign began in earnest, with retaliation by Loyalists through the bombing of civilian areas in the South. At the same time, the British authorities believed there was an increase in the number of incidents in Northern Ireland perpetrated by Republicans crossing the border from the Republic. The British Army estimated that ‘terrorists based in the Republic have been responsible for at least 497 incidents in 1973’.[19] The spread of the conflict from Northern Ireland to Britain and the Republic of Ireland worried the British and Irish authorities, although there was little Anglo-Irish co-operation at this stage.

The bombing of two Birmingham pubs in October 1974 led to the newly installed Wilson government to rush through the Prevention of Terrorism Act (Temporary Provisions) Act 1974. As well as extended powers of detention for those suspected of terrorism offences in Britain, the Act also gave powers to regulate the travel of people from Northern Ireland to England, Wales and Scotland (Great Britain) and exclude/deport those suspected of being involved in terrorism offences (related to the conflict in Northern Ireland – the PTA did not extend to the other forms of international terrorism on the rise in the 1970s). In 1976, the Act was amended to cover people travelling from the British mainland to Northern Ireland, but crucially neither act dealt with suspects travelling between Northern Ireland and the Republic of Ireland. The British authorities still relied on policing the border though a series of checkpoints.

In the same year, the Northern Ireland Office warned that policing the border in this manner was still involved massive amount of manpower, with a report stating:

Since 1971 nearly 20% of regular Army manpower in the Province has been devoted to maintaining the integrity of the Border areas and the Border itself. Experience has shown that because of the length and nature of the Border, the Army, no matter how many men they deploy cannot ensure total security.[20]

Furthermore, the report argued that border area was not topographically ideal for surveillance and certain technologies, such as radar and unattended ground censors, had limited success in helping the authorities detect subversives crossing the border.[21]

To overcome this, the report revisited the idea of laying mines, erecting wires or some other kind of immovable physical obstacle across the border to restrict illegal crossings. However it was felt that the use of either mines and wires had ‘an unpleasant “East German” connotation and would be indicative of a siege mentality’, with the added problems that ‘[m]ines would be dangerous and wire would be unsightly’.[22]

In 1977-78, Lord Shackleton undertook a review of the Prevention of Terrorism Act 1976 and despite suggesting that exclusion orders be subject to periodic review,[23] there was little revision on the issue of cross-border terrorism and subversion. At the same time, the temporary provisions of the 1976 Act were up for renewal. At this point, the Home Office briefly considered whether the transformation of the checkpoint system into a more formal border control system across the Irish border would help in the fight against Republican (and Loyalist) violence. However it was soon concluded that, like the checkpoint system, control of the border between Northern Ireland and the Republic would still require a large amount of manpower.[24] A report prepared by the Home Office stated categorically, ‘A system of full immigration control would be costly, most difficult to administer, and of limited effectiveness’.[25]

Although the conflict in Northern Ireland has, for the most part, ended, it would be wise heed this warning about the difficulty of implementing an immigration control system between Northern Ireland and the Republic of Ireland. Since the creation of the Republic of Ireland in 1949, there have been no immigration restrictions between the UK and Ireland and the only controls have been applied have been the exclusion orders under the Prevention of Terrorism Acts (which were made redundant in 2000 by the Terrorism Act). To establish a new border control system at the land border between Northern Ireland and the Republic would be a blow to the peace settlement forged in 1998, and to wider Anglo-Irish relations.

[1] ‘Control of Northern Ireland Borders: Preliminary Report’, 17 May, 1971, p. 1, CJ 4/424, National Archives, London.

[2] ‘History of the Partial Closure of the Border in 1970’, 17 May, 1971, CJ 4/424, NA.

[3] Ibid.

[4] Ministry of Home Affairs, ‘Border Control: Vehicle Documentation’, p. 1, 1 February, 1973, CJ 4/424, NA.

[5] Letter from Northern Ireland Office to Northern Ireland Command, 30 March, 1973, CJ 4/424, NA.

[6] Government Security Unit, ‘Control of the Border’, p. 1, 30 March, 1972, CJ 4/424, NA.

[7] Ibid,

[8] Ibid, p. 2.

[9] Ibid, p. 2.

[10] Ibid, p. 2.

[11] Central Secretariat (Stormont), ‘Vehicle Documentation in Border Areas’, 13 November 1972, p. 4, CJ 4/424, NA.

[12] Ministry of Home Affairs, ‘Border Control’, p. 4.

[13] Ibid.

[14] Central Secretariat, ‘Vehicle Documentation in Border Areas’, p. 6.

[15] Ibid., p. 7.

[16] Ibid., p. 10.

[17] Ministry of Home Affairs, ‘Border Control’, p. 7.

[18] ‘Control of Northern Ireland Borders’, p. 1.

[19] Lt. Colonel Reynolds, ‘Border Security’, 30 January, 1974, p. 1, CJ4/810, NA.

[20] Northern Ireland Office, ‘’Picquets and Unmanned Devices on the Border’, 2 December, 1976, p. 1, CJ 4/1758, NA.

[21] Ibid., p. 4.

[22] Ibid., pp. 6-7.

[23] Lord Shackleton, Review of the Operation of the Prevention of Terrorism (Temporary Provisions) Acts of 1974 and 1976 (London: HMSO 1978) pp. 39-41.

[24] ‘Difficulties Over Proposal for Immigration Control Between the United Kingdom and the Republic of Ireland’, n.d., HO 344/336, NA.

[25] Ibid.