Murray McCully will not be resigning from the Cabinet over his ministry's inept handling of the alleged sex attack involving a staff member at the Malaysian High Commission.
He is under no constitutional obligation to do so. He is under no substantial political pressure (as yet) to do so. He has done nothing that is politically shady or morally dubious which would give his opponents the grounds for demanding that he does so.
Even if the foreign minister did offer his resignation, it is most unlikely that John Key would accept it. In short, it is going to take much more than the victim in the alleged attack calling on him to step down for that to actually happen.
Tania Billingsley's beef with McCully stretches beyond being deeply unhappy about the Ministry of Foreign Affairs blunder that saw her alleged attacker return to Malaysia. She has accused McCully of being intent on pinning responsibility and blame for the subsequent diplomatic brouhaha on to everyone else but himself. She is right. But McCully made no apology for doing so.
As a minister, he has the right to be able to rely on the ministry's officials to keep him fully briefed on things he needs to know about. Instead, he was kept largely in the dark.