Former Resource Rent Tax Australian Tax Office deputy commissioner Stephanie Martin.

Former Resource Rent Tax Australian Tax Office deputy commissioner Stephanie Martin. Photo: Andrew Meares

The head of the tax department responsible for collecting the federal government’s minerals resource rent tax has just quit her position, throwing doubt over the agency’s ability to collect the tax.

Stephanie Martin, a deputy commissioner at the Australian Taxation Office, was until last month heading the ATO’s resource rent tax team which had responsibility for collecting the Minerals Resource Rent Tax and Petroleum Resource Rent Tax.

But Ms Martin retired from her position quietly on March 7 and it is understood no replacement has been found for her.

The minerals resource rent tax must still be collected by law and will not be repealed until the new senate takes shape from July 1.

Ms Martin could not be reached for comment.

The news comes after the Tax Office made a major reshuffle of its organisations in the months following the Coalition’s September election win.

The ATO Commissioner, Chris Jordan, wrote to all employees on 20 November last year warning them about the organisation’s need to reduce staff.

Mr Jordan said up to 900 full time equivalent positions would need to go to help the Tax Office achieve a financially sustainable 2013–14 budget position.

As part of those efforts, about 100 of the 140 people working on the minerals resource rent tax team were redeployed to other parts of the organisation.

According to the ATO, there are now just 30 staff making sure that people are paying the tax, with 5 more chasing outstanding MRRT and PRRT returns from the 2012-13 year.

An ATO spokesman told Fairfax Media these lower staff numbers were still sufficient to ensure that the resource rent tax was being collected.

“The MRRT will be a two year tax if it is repealed by 1 July 2014 as the Government intends,” the spokesman said.

“Our current workforce is effectively administering the tax with these considerations in mind. Additional staff are available if required from other areas within the Public Groups and International team.”

But the Shadow Assistant Treasurer, Andrew Leigh, said news of the departure of Ms Martin was not good for the collection of the mining tax.

"To score a cheap political point, this government is cutting back on enforcement of the mining tax, which Joe Hockey projects will raise $1.8 billion in 2016-17,” Mr Leigh said.

“Every dollar foregone means higher taxes or fewer services for ordinary Australian families."

Treasurer Joe Hockey, who is travelling in Washington DC, could not be reached for comment.

The Tax Office is a separate agency from the Australian government with control of its own operations, including staffing levels.

The ATO would not comment on Ms Martin’s departure.

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