The eight-and-a-half-year prison sentence for the Auckland businessman who threatened to poison baby milk powder is a deterrent to others, Fonterra's boss says.
Sixty-year-old Jeremy Kerr's attempts to blackmail Fonterra and Federated Farmers cost the companies involved and taxpayers $37 million.
The dairy giant and farmer group received letters in November 2914 containing deadly samples of the pesticide 1080 and an ultimatum to ban the poison or infant formula would be contaminated with it.
Prime Minister John Key says Kerr's threats that could kill babies were "just despicable behaviour".
And Fonterra Managing Director Maury Leyland says the idea of that happening is terrifying.
"And that's why the sentencing, I think, denounces the crime and provides an appropriate deterrent," said Ms Leyland outside the High Court in Auckland.
A market wide effort to screen and test products was launched after the threat, causing international shockwaves.
In the High Court in Auckland, Justice Geoffrey Venning said the potential impact on New Zealand's trade relationships with China and other countries was extremely serious.
Mr Leyland told the court the offending "was a direct threat to our company, our farmers incomes and the New Zealand economy".
The police admit the investigation was like looking for a needle in a haystack.
"We identified 2600 people that we believed were potentially of interest and we managed to whittle them down to one," said Detective Superintendent Andy Lovelock of Auckland Police.
Kerr was caught after leaving vital DNA evidence on a later letter he sent to police.
Kerr says he wanted 1080 to be used more responsibly. The court ruled the threat was made for financial gain. He had business interests in a rival poison called Feratox and would receive royalties from increased sales of it if 1080 was banned.