If you are wondering what gives the Minister for Justice the power to apply to the High Court for such a staggeringly broad surveillance regime, well, the answer is that Section 4 of the Communications (Retention of Data) (Amendment) Act [You know, the one that may not actually be in effect because they forgot to put it through TRIS] inserts a whole sequence of steps around such an application.
https://www.irishstatutebook.ie/eli/2022/act/25/enacted/en/print#sec4