Well I mean, due to the separation of powers, the high court are separate from the parliament and the politicians. Just for the exact case of being able to decide against what a parliament had chosen. In this case you’re still disagreeing with the governnent decision to indefinitely hold illegal immigrants, who in this case are legitimate asylum seekers, even while agreeing with the judicial process applying the constitution to that parliamentry decision.

Hope that helps reconcile your feelings since you can rest assured your still disagreeing with part of the government.