The Ombudsmen's office is being criticised for tightening the rules on complaints from overstayers about their dealings with Immigration New Zealand's Pacific division.
Thirteen overstayers were granted residency this year after the Ombudsman ruled they had been misled by the division in 2005, with promises of jobs and residency.
Lawyer Richard Small says a three-month deadline and tougher criteria agreed between the Ombudsman and Immigration New Zealand have made further complaints virtually impossible.
He says that is profoundly unfair on dozens of overstayer families who have waited more than five years for a fair hearing, and who are now at risk of being deported.
The Ombudsmen's office says it is considering Mr Small's request to extend the deadline for new complaints.