It's been revealed foreigners with a criminal history of polluting waterways now own a pristine piece of Taranaki farm land.
The Overseas Investment Office (OIO) approved the sale of Onetai Station to Argentinians Rafael and Federico Grozovsky -- despite knowing the brothers' history.
The OIO also didn't inform the Government ministers who signed off on the purchase.
Minister of Land Information Louise Upston is unimpressed and says the agency dropped the ball.
"The person who was considering it had information that they didn't pass on to ministers, and that is a problem."
New Zealand First leader Winston Peters says the OIO is a disgrace.
"The Overseas Investment Office is just a rubber stamp and it's a disgrace actually for a nation to have such a body in charge of any of its policing of the rules."
The Grozovsky brothers were convicted just two years before the OIO approved the sale, because a tannery they owned in Argentina was leaking cancer-causing chemicals into a river.
Media reports from Argentina at the time state the company's drains carried liquid waste into the Lujan river, producing high levels of contaminants such as hexavalent chromium, which is a dangerous carcinogen.
The chemical can cause irreparable damage to soil and water and poses a serious risk of skin lesions, lung disease and cancer to the affected population.
Last week it also emerged that the Grozovsky brothers had links to the law firm at the centre of the Panama papers scandal.
Despite this the OIO stood by its decision to pass them on good character grounds.
Labour then found the conviction through a Google search, and today it has emerged that is how the staff member at the OIO found it too.
The sale is now under review by the OIO.
If it finds the Grozovsky brothers failed to tell them about the prosecution, they could be kicked off the farm.
This is an option the Government would consider, according to Ms Upston.
"One of the enforcement actions available to the Overseas Investment Office is to force the sale of the property, absolutely," she says.
In a statement, the OIO called the blunder "a regrettable lapse".
The OIO noted that it's made changes since the sale, including appointing an "experienced person to undertake web searches... using search terms like 'conviction' and fraud'".