Auditor-General Lyn Provost has decided a full inquiry into KiwiRail's purchase of rolling stock is not warranted.
Labour's Dunedin South MP Clare Curran asked for the inquiry last August, into four purchases of railway rolling stock in recent years from China Northern Locomotive and Rolling Stock Industry Corporation (CNR).
Provost's office said correspondence from Curran in November and December 2012 raised further concerns about the value for money of these purchases and the effect of the purchases on the future of KiwiRail's workshops in Hillside, Dunedin.
"To assess whether the questions raised by Ms Curran warranted a full inquiry, we met with some relevant staff and obtained background information from KiwiRail on each purchase," the office said.
"The work involved in large purchases of this kind can extend over several years; we have therefore reviewed a substantial amount of documentation dating back to 2005.
"Because of the passage of time and the change in ownership of the company in 2008, we were careful to then take the time to locate and access the relevant records and people at KiwiRail who had been involved.
"Given the highly technical nature of the purchasing process, we used specialist assistance to complete our assessment."
But it said enough preliminary work had been done to satisfy the office there was nothing to suggest decisions to buy locomotives and wagons from CNR were made for anything other than normal business and commercial reasons.
"The processes followed by KiwiRail appear reasonable, the relevant evaluations have been carried out properly, and we have seen no evidence to suggest improper influence over these decisions," the office said.
"We have therefore concluded that further investigation, in the form of a full inquiry, is not warranted."
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