Haggett also gave the school "significantly and falsely inflated" results for the school's overall performance in the Cambridge and National Certificate of Educational Achievement (NCEA) exams in 2011 and 2012.
The tribunal said the school wanted to offer Cambridge exams for its Religious Education students, but the exams were only available in June of each year - the end of the school year in Britain, but only half-way through the school year here.
"However the respondent [Haggett] reported to the school (including the principal) that he had checked with Cambridge and it was possible for the students to take the Cambridge Religious Education exams in November 2013," the tribunal said.
"The respondent announced examination dates and a number of final-year Religious Education students sat what they believed were Cambridge Religious Education papers over three days in November 2013."
The school's headmaster at the time, Kieran Fouhy, told the tribunal that he started asking questions early in 2014 when the exam results had not been received back from Cambridge.
"When asked, the respondent reported that he had sent the papers to England but that [Cambridge] claimed they had not been received. The respondent claimed Cambridge had said they had lost them."
Another deputy headmaster, James Bentley, who is now the headmaster, then contacted Cambridge and "discovered that there had never been New Zealand sittings for Cambridge Religious Education in November 2013".
Haggett then admitted that he had "constructed" the exam paper but "didn't know what had happened to the exam answers".
"Mr Bentley gave evidence that in November 2015 the respondent's former partner brought to him what were clearly the exam papers concerned which she had found hidden in the bottom of the cupboard in the house she had shared with the respondent," the tribunal said.
Bentley also told the tribunal that he had checked the NZ Qualifications Authority website in February 2013 and found "serious anomalies" between the data that Haggett had reported to the school for the two previous years and the school's actual results.
"The results for 2011 and 2012 were significantly and falsely inflated," the tribunal said.
"As an example of the magnitude of the inflation, the investigation [for the tribunal] by Jacky Young reported that in 2011, for level 3 NCEA, pass rates were reported as 83 per cent by the respondent, whereas the true pass rate was 61 per cent."
Fouhy told the tribunal that he became concerned for Haggett's mental health after he admitted fabricating the Cambridge exam, and referred him to counselling.
However Haggett resigned and agreed to leave the school on August 4, 2014, on full pay until January 27, 2015. He is believed to have returned to Britain in May 2015.
Haggett arranged to appear by telephone at a tribunal hearing in Wellington on November 29 last year, but emailed on November 28 saying he would be unable to appear because of "a family matter". He was not represented at the hearing.
He provided a written statement alleging "a lack of support at the school to assist him and a failure of the principal to establish parameters for his role".
He also noted that his father died in Britain in June 2015 and that he broke up in that year with his partner, a New Zealand resident. He asked for name suppression to protect his family.
"He referred to his daughter, now 3 years old. He does not apparently have any current contact with her," the tribunal said.
It noted that the girl had a different surname and rejected his application for name suppression.
