Then finance minister Bill English was interviewed by police in Southland about Todd Barclay's recording of his staffer.

Audio of the police interview with Bill English that sank Todd Barclay's career has been released.

The April 2016 police statement eventually led to Barclay stepping down from Parliament under police investigation.

Under media pressure English himself released an unredacted transcript of the statement in June, when Newsroom revealed that he had been a witness in the initial police investigation, but the audio has never surfaced.

SIMON MAUDE/STUFF Bill English eventually released a transcript of the interview after media pressure.

Stuff obtained the file under the Official Information Act. Some minor redactions remain.

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Earlier English's office successfully pushed to have his identity withheld from information releases relating to the Barclay matter.

Barclay, then the National Party MP for Clutha-Southland, was accused of secretly recording the conversations of his staffer Glenys Dickson.

It is illegal to record a conversation you are not a part of in New Zealand.

Barclay denied the charges and refused to meet with police, leading to the initial investigation closing.

STUFF Former Clutha Southland MP Todd Barclay moved to London after the recording scandal.

But in July Newsroom revealed several new details about the matter, including that English had been interviewed.

English released the transcript of the interview, in which he told police that Barclay himself had told him about recording the staff-member.

"I had a conversation with him regarding Glenys Dickson leaving his office and he said to me that he had recordings of her criticising him," English told Detective Superintendent Peter Read (4.20 in the audio above.)

ROBYN EDIE/STUFF Bill English and Todd Barclay (file photo).

"He said he just left the dictaphone on."

English was deputy prime minister at the time, although he describes himself as simply a member of Parliament and the finance minister.

Barclay admitted that he may have misled media with "specific" comments but refused to resign.

Days later he announced that he would not stand for Parliament again.

Instead he served out the rest of his term in office, taking several weeks off work and avoiding any media questions.

Barclay has now moved to London.

Police reopened the investigation in light of the new evidence but have been tight-lipped on whether they have sought an interview with Barclay or intended to prosecute.

A police spokesperson refused to comment on Tuesday, other than to say the investigation is "ongoing". It is almost four months since it relaunched.

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