A former Auckland cop has narrowly avoided prison after dodging nearly $300,000 in tax, while also trying to hide details of his offending the Weekend Herald can reveal.

Gregory Raymond Fallon, 42, was convicted and sentenced yesterday in the Auckland District Court by Judge Nicola Mathers to nine months' home detention and 150 hours' community work.

To avoid a prison term, the starting point set by Judge Mathers, the ex-constable relied heavily on his previous good standing in the community and his early guilty plea to 44 charges of tax evasion to have his sentence reduced.

The maximum penalty was a five year prison stint.

Fallon's police career, which he served over two separate periods, was largely as a member of the Eagle helicopter crew and on police motorbikes.

He first made headlines in 2003 when he was one of two officers to leap from the helicopter to save a drowning couple, who had been lost at sea near Rangitoto Island.

He has also been credited with saving "many lives" as a surf lifesaver and placed his police career on hold to help with the Christchurch earthquake rebuild.

However, Fallon's dramatic fall from grace came when he said he made the "grave mistake" of trying to run a business and be a police officer at the same time.

The Weekend Herald can now reveal he has twice failed to pay large sums of tax owed by his two companies.

And total amount evaded during his 27 months of offending was just over $283,600.

He was the sole director and shareholder of Asbestos Management New Zealand Limited, incorporated on June 8, 2015.

In September 2016, the Inland Revenue Department (IRD) told Fallon, who was solely in charge of his company's finances and wages, that it was conducting an audit.

Fallon's company had failed to file any GST or pay as you earn (PAYE) returns, while he had also failed to file his personal income tax return during the past year.

In December 2016, Fallon filed some of the outstanding tax returns and the next month told IRD he intended to file all the returns but just didn't have time.

"It was low [on my] priority list ... and [I] just ran out of time," he said, having also re-joined the police after leaving the force in 2013.

In March 2017, IRD sent Fallon a letter expressing concerns about his continual failure to file tax returns and asked for a reason why he shouldn't be prosecuted.

Fallon again replied that he was too busy and over committed with work to adhere to his tax obligations.

He said he'd hired a new tax agent to manage the day to day running of his business.

At another meeting in May 2017 with IRD, Fallon said he had no intention to conduct a dishonest business and feared that a prosecution would destroy his police career.

IRD gave Fallon a month to present a plan to repay the owed tax, but he failed to do so.

A final chance was given to the police officer on October 2 last year, but he again failed to make a single voluntary repayment.

Even after he was charged and pleaded guilty, Fallon still did not attempt to pay back the tax, Judge Mathers said.

Since then he has made a voluntary payments of $20,000, while his company is about the be placed into voluntary liquidation.

It was not the first time Fallon had issues with IRD, however, and first had tax problems when the sole director and shareholder of Villa Renovations Limited.

From 2008 to 2014 the company filed 50 tax returns, but only four were filed on time and none were filed between April 2014 and January 2016, when the company was removed from the companies office register.

Some $60,000 of unpaid tax from the renovation company has been written off, deemed to be unrecoverable by IRD.

As police and the Weekend Herald learned of Fallon's offending, both sought access to court documents - but Fallon objected.

He said the circumstances had chanced since he pleaded guilty and allowing police and the press to view the files would be detrimental to him and his business prospects.

However, Judge Mathers did not think it was appropriate for Fallon to "be seeking to renegotiate the summary of facts" after his admission of guilt.

Fallon's counsel, Tamina Cunningham-Adams, said her client appreciates he did nothing when he should have done something.

Inspector Jim Wilson, the relieving District Commander for Auckland City Police, said Fallon quit in last month.

Judge Mathers said Fallon had "quite rightly resigned as a police officer" but did not consider his past career as an aggravating feature.

"You buried your head in the sand because of the share situation you found yourself in."

A police employment investigation was due to commence following the outcome of the court proceedings, however, there will now be no internal investigation because of Fallon's resignation.

Fallon is now working as a motorcycle instructor.