Alan Shatter (Dublin South, Fine Gael) | Oireachtas source

Technically, my understanding is that it would be very unusual for such an action to affect the entire country. Theoretically, if the entire country were under threat, then it would be possible. The reality, as happened in Boston recently, is that an area may be identified as having a threat and coverage would be shut down there. It would be highly unlikely that such an event would apply to the entire country but there are circumstances in which it could. For example, it could apply to the entire country if there were serious and substantive intelligence available to an Garda Síochána which indicated a major incident would occur within a particular timeline but there was not absolute clarity as to the location at which it would occur. Under the circumstances in which these powers have been used in other jurisdictions, it has been normally confined within a discrete area. The technology available to mobile telephone companies allows them to do that.

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