Immigration New Zealand rejected a man's application to live in New Zealand because it could not believe an older woman could fall in love with a young man, says his immigration adviser.
Immigration consultant Tuariki Delamere said the belief was "appalling".
Indian man Balwinder Singh, 22, and Glyn Kessell, 59, got married three months after they met last year.
Singh applied to live in New Zealand under the partnership category, only to be declined after being assessed twice by different officers, Immigration New Zealand's (INZ) Michael Carley said.
The decision was made after an "extremely detailed" assessment, which included visiting the couple at their home and interviewing them both, Carley said.
"The couple got married after an uncommonly short three-month courtship," he said.
"INZ is not satisfied that the couple are in a genuine and stable relationship which is likely to endure."
To convince the department, couples need to prove they had been living together in a genuine and stable relationship for a year or more, said INZ's website.
They also need to have met before they made their residence application.
But Delamere said he had seen the transcripts of the meetings, and there was nothing in them to suggest the couple were not in a genuine relationship.
"It was declined because they had 38 years difference in age, and because of culture and religion," he said.
"That's illegal, and a breach of discrimination laws in New Zealand."
He said it was hypocritical the Government could congratulate politicians like Rodney Hide and Paul Swain when they married younger women, and then have a government department rejecting a case like Singh's and Kessell's based on age.
The couple, who intentionally missed their deadline to appeal the decision yesterday due to cost, would now appeal to the "much cheaper" Immigration and Protection Tribunal, Delamere said.
That could give Singh more than a year of extra time in New Zealand before he would have to face possible deportation.
"He can't be arrested until the tribunal has made its decision, which could take around 18 months," Delamere said.
Delamere would also complain to the ombudsman about the decision.
Immigration New Zealand said 15,068 partnership visa applications were lodged between July 1 2012 and June 30, 2013. Of those 668 were declined. Data about rejections because of age differences was not available.