It's thought a widespread migrant worker exploitation discovered in the kiwifruit industry in the Bay of Plenty is only the tip of the iceberg.
A Government investigation has found more than half of Bay of Plenty's kiwifruit audited employers fail to meet the bare minimum of basic employment standards.
Immigration law specialist Richard Small told Larry Williams it's a long-standing problem.
Listen to immigration specialist Richard Small speak to Larry Williams on The Mike Hosking Breakfast in the Soundcloud embed below:
"It's fairly obvious that it crops up wherever you have people that are vulnerable and desperate combined with unfortunately employers, not all it's important to say, who are willing to take advantage of that."
Sub contractors are said to be the problem with migrant worker exploitation, Mr Littlewood said, as some unscrupulous employers use middle men or middle women and the sub contractors do the employing, and they are a law unto themselves in most cases.