According to Rail Minister Winston Peters, KiwiRail's $8 million expenditure on management consulting is intolerable.

On December 6, 2023, less than a week before the government announced it was abandoning the Interislander replacement project iReX, KiwiRail hired McKinsey and Company to conduct a strategic review on how to improve performance for rail freight and the ferries.

According to Finance Minister Nicola Willis, the charge was unjustifiable and unacceptable. Using the excuse of business sensitivity, KiwiRail has declined to disclose the cost.

The Ombudsman looked into whether the payment amount should be made public under the Official Information Act in response to the NZ Herald's concerns, and at first he decided KiwiRail didn't have to.

But that ruling was overturned on Friday after the Ombudsman changed his mind in response to a second complaint, supported by former Kāpiti Coast District Councillor and government relations consultant Gwynn Compton.

Winston Peters, the Minister for Rail, claimed in a statement that KiwiRail had not informed the government that it had hired the company until two months after doing so. He said that if KiwiRail had told the government of its intentions, the payment would not have occurred and that it was inappropriate.

Peters stated that McKinsey's services were offered in a legal and competitive way, thus they are not condemning the firm. The choice to pay that amount is being criticized. Hiring management consultants should not be the solution to a challenging balance sheet. If they had shared their ideas with them, this would not have occurred. Reducing cost, improving service quality, and expanding the client base should be the answer, and KiwiRail is now achieving just that.