The primary job of the civilian guards on duty at Massereene Barracks was “to deter terrorist infiltration of, and attack on, military establishments”, according to the Ministry of Defence.

Yet a year ago there were sufficient doubts about whether they were fit for such a role - given the rising threat from dissident republican terrorists intent on killing members of the security forces - for the MoD to set up a review.

It was due to have reported at the end of last year with recommendations for making the Northern Ireland Security Guard Service (NISGS) more effective; however, it has yet to do so. “This work is still ongoing,” the MoD said yesterday.

When the service was established in 1998 the aim was to create a community-friendly guard force that would satisfy the political sensitivities of the Province in line with the Good Friday agreement, military and political sources told The Times.

The guiding principle behind the guarding of army bases in Northern Ireland is as much about Ulster politics as it is about security, according to former ministers and ex-military commanders.

With the Good Friday agreement plotting the course for a return to normality in the Province, there was distinct opposition to having “British army soldiers in combat uniform armed with SA80 rifles standing guard”, one senior former commander said.

“The aim was to have a guard force that was in tune with the community,” Doug Henderson, the Labour Armed Forces Minister from 1998 to 1999, told The Times.

Recruits were largely found from Northern Ireland and were often ex-servicemen. Like their counterparts on the mainland, they were trained to fire sidearms and non-automatic carbines. But to underline the softer image required to measure up to the political sensitivities of guarding bases in the Province, the civilian security officers of the NISGS were banned from wearing combat fatigues and were put into blue uniforms. They are officially described as special constables.

The force is 450 strong and its members are trained to use their weapons in anger only for self-protection purposes and the protection of others. The MoD said their role was to control access to each of the regular military locations and to be ready for “first-response tasks”.

On the mainland, there is a mixture of forces available for guard duties. In addition to members of the Armed Forces, there is the 3,500-strong MoD Police, who guard sensitive places such as nuclear submarine facilities; the Military Provost Guard Service (MPGS), armed ex-servicemen employed at many of the military facilities; and a non-armed MoD Guard Service, which is responsible for the security of MoD property and buildings.

The MoD insisted that the principles of guarding duties were identical. The MoD Police on the mainland, however, conduct armed patrols inside and outside the wire and follow standard police rules on the use of firearms. The NISGS is allowed to carry out only internal-base patrolling.

The civilian guards are paid civil service rates for supervisors, with a salary band ranging from £13,881 to £17,072, plus an “arming allowance” of £636.

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