A judge had little option other than discharging an Israeli couple caught with more than 6kg of dried cannabis, a legal expert says.
Israeli husband and wife Daniel and Hadas Surdri pleaded guilty to cultivating charges in the Ashburton District Court on Monday.
Judge Noel Welsh was persuaded by their lawyer Bevan Coombes to discharge them without conviction in return for a $2000 donation to the Salvation Army.
A police raid on the couple's property on June 12 uncovered evidence of 54 harvested plants, a master plant - used to take propagation cuttings, and more than six kilograms of dried cannabis - the product of a sophisticated indoor growing operation.
One person needed medical attention after being overcome by cannabis fumes.
The couple claimed the cannabis was for their own use, and Mr Coombes asked Judge Welsh to hold back from convicting them on this basis, combined with their good reputation and because it would stymie their plans to travel to Tanzania to do voluntary work.
When charged, the Surdis already had airline tickets to return to Israel on July 3.
The Guardian has fielded several calls relating to the matter.
One local man said the sentence, or lack of, "stunk".
"I know New Zealand citizens caught with a little bit of pot who can't travel because they have a conviction," he said.
The onus was on the offender to prove they were not supplying or selling cannabis if caught with more than 28gms in their position.
"It's the biggest drug bust around here in recent years and they say it's personal use - it's not humanly possible to smoke that amount of pot before they leave - they would have to get through a pound (454gms) a day.
"And $2000 is nothing - that haul could be worth $30,000-$40,000 on the street - and that would be selling it by the pound."
However, Professor Kevin Dawkins, from the University of Otago Faculty of Law, said Judge Welsh was well within his rights.
He could only comment generally, on the cultivation charge which carries a maximum sentence of seven years' imprisonment.
A sentencing judge had the power to exercise dispensation if the consequences of a sentence were out of proportion to the gravity of the offending, he said.
This could relate to adverse professional consequences - siting lawyers, accountants and real estate agents as professionals who, if convicted of drug-related matters, would be unable to practice.
Limiting the offenders' ability to travel could also be seen as a reason to discharge without conviction. This might apply to professional sports people, or those who were required to travel for their work.
Professor Dawkins agreed that people found in possession of more than 28gms, or 100 cigarettes containing cannabis, were generally presumed to be selling or supplying, but a lack of evidence - such as lists of names, snap lock bags, tin foil or cash, could mitigate this.
He said offenders who were discharged without conviction were in effect acquitted, and did not have to declare the charge at New Zealand, Australian or UK borders.
But, Professor Dawkins said Judge Welsh probably didn't have many options - as the couple in question already planned to leave the country.
"It's quite common for people to get home detention (for cultivating cannabis) but that's not an option, and community detention is not appropriate - neither is imprisonment," he said.
"They had no property here - so there was no chance of forfeiture.
"The judge would have been in a predicament."