A man who has been described as one of the country's most prolific methamphetamine manufacturers has had his life sentence quashed and replaced with a 20-year prison sentence.

Christian Paul Clifton will have to serve a minimum of 10 years behind bars before he can apply for parole, the Court of Appeal said in a written judgement today.

Clifton was sentenced to life at the Auckland District Court in September 2011 for 10 charges of manufacturing methamphetamine and other concurrent finite terms of prison for conspiracy to supply and supply of the drug.

He appealed against his sentence on the basis it was manifestly excessive.


Sentencing judge Judge Roy Wade described Clifton as "one of the country's most significant manufacturers" who had been making the drug since 2000.

In just five months in 2009, he manufactured 10 batches of P with a street worth of more than $1.3 million.

Clifton said Judge Wade erred in judging him to be the primary player in a manufacturing and supply network.

But Clifton said he answered to his main financier William James MacFarlane.

MacFarlane was arrested in the same police operation that netted Clifton and he was sentenced to 14 years prison on two charges of manufacturing methamphetamine.

Clifton said Judge Wade also made an error in believing Clifton manufactured the drug for profit, when it was because of gang standover tactics.

However, the Crown said the scale on which Clifton had manufactured had placed him amongst the "most extreme" drug offenders.

He manufactured while on parole for similar offences, the Crown said.


At sentencing, Judge Wade said a finite sentence would be "wholly crushing" for Clifton and a life sentence was more merciful and positive.

If he gave a finite sentence, Clifton would be sentenced to 21 years jail with a minimum non-parole period of 10-14 years.

Justices Ellen France, Patrick Keane and Forrest Miller agreed the sentence was manifestly excessive.

"An indeterminate sentence of life imprisonment is not, as the judge held, more merciful than the determinate sentence...he would have otherwise imposed," they said in their ruling.

A parolee would be monitored and could be recalled to jail. "An offender sentenced to life imprisonment is subject to that regime for life," they said.

They also said the sentence did not stand up to scrutiny when compared with other similar cases.