The minister can be involved in the challenge function. The challenge function simply asks if something makes sense. Certainly, when it comes to the issue of identifying the priority for resources, ministers are very much involved in the priority-setting for how our resources are expended.
Hypothetically, that can occur—and probably has occurred—where we've identified that something was seen to be not affordable, and in terms of the priority setting across the department, that's probably an appropriate role for the minister to play.