Immigration New Zealand failed to inform Minister Iain Lees-Galloway that Karel Sroubek returned to the Czech Republic in 2009, after being told the information in 2012.
Mr Lees-Galloway originally granted the Czech drug smuggler residency, a decision that changed after a review was launched. Sroubek is now liable for deportation after Mr Lees-Galloway received new information that contradicted that which he used to make his decision.
In light of the new information Mr Lees-Galloway today expressed his concern he wasn't made aware of the information in 2012.
Documents obtained today show a Customs intelligence analyst informed Immigration NZ that Sroubek had returned to the Czech Republic in 2009. Sroubek was also known as Jan Antolik.
"ANTOLIK is a person of interest to NZ Customs and there are a number of reports that may be of mutual benefit to both departments, particularly with his claim that he would be in danger if he was deported to the Czech Republic," a March 1, 2012 email reads.
"It was reported that he had travelled Auckland - Bangkok - Frankfurt return. From Frankfurt he had hired a car and driven to the Czech Republic," a March 12, 2012 email said.
Mr Lees-Galloway said that today's information release "shows that the current process is not sufficient when Ministers are making decisions on complicated cases like this".
"I am particularly concerned that I was not made aware of the 2012 tip off from Customs that Mr Sroubek had travelled back to Czech Republic in 2009 when making decisions about this case. This material has only come to light in the process of pulling together the OIA response.
"These deficiencies highlight why it is appropriate that Immigration NZ are reviewing the process of developing these files."
Immigration New Zealand launched an investigation on November 1, 2018 into the residency application of Karel Sroubek.
Mr Lees-Galloway told media at the time he received new information that contradicted that which he used to make his decision to grant residency to Sroubek.
On November 28, Sroubek was found to be liable for deportation after a review by Immigration NZ.
Mr Lees-Galloway announced the findings, saying "as a result of that review, Immigration determined that Mr Sroubek may be liable for deportation on grounds that I had not previously considered".
He said there was some information INZ compiled that was not available to him when he made his original decision.