Brian Out on Bail

Remember when Brian was out of jail on bond, living by himself in an apartment and Rachel kept visiting him? A condition of Brian's being out on bail was that he have no contact with Rachel. The Garda wanted to do anything they could to make life hard for Brian. Chief among their goals was to get him back in jail and a good way to do that was to catch him in the act of being with Rachel which would violate his bond and return him to custody.

We got to watch the Garda agonizing over this in episode after episode and, all the while, Rachel was coming and going at Brian's apartment with impunity.

All they needed to do was set up a surveillance on Brian's apartment (they knew where he lived) and as soon as Rachel went inside, bust him. Did they think to do this? No.