Two immigration-accredited businesses have been reported to authorities, accused of charging migrants money in exchange for jobs and visas.
An immigration lawyer says a new work visa has prompted a free-for-all, with migrants paying up to $40,000 to overseas agents and New Zealand employers, because Immigration New Zealand (INZ) was not carrying out full checks on migrants' work experience.
INZ denies that, and said if employers have charged migrants they will lose the accreditation that allows them to recruit overseas workers.
Lawyer Alastair McClymont said over the summer they started receiving reports of agents charging migrants for job offers and visas in India, Vietnam and elsewhere.
"Offshore agents, or other immigration advisers, or recruitment people - we're hearing the same story coming up again and again about immigration advisors and agents in India who are demanding $40,000 for jobs and they basically provide all the documents," McClymont said.
"They could get work visas for anybody who could front up with the money."
His staff had already by that time noticed INZ was no longer checking on applicants' previous experience through work references.
He fears some of the fees paid to agents was going to employers, who may also be forcing migrants to repay some of their wages - to refund the higher pay rate they need to qualify for the new visa - in a process known as wage recycling.
The Accredited Employer Work Visa (AEWV) was the government's flagship immigration policy introduced last year, designed to simplify the process and reduce exploitation.
It used salary levels, rather than specific job roles, to decide who should get employer-supported work visas. The policy required employers to gain accreditation through checks on their business and previous compliance, which was followed by a job check - to see no New Zealanders were available to do the work - and finally a work visa application.
Central to the plan was migrants being paid at least the New Zealand median payrate, with temporary exceptions later introduced for some roles in the hospitality, construction and aged care sectors.
Opponents said those criteria would restart a cycle of fraud, wage recycling and exploitation, similar to the issues with international students over the last decade.
Employers found the AEWV process cumbersome, costly and long and has hampered them recruiting overseas workers. INZ might be skipping work references to speed up the visa process, McClymont said.
He said migrants would be the ones punished for the fraud if they were found out.
There were people who should not be getting a work visa at all because they were unskilled, and employers - who may genuinely not have known they were recruiting unskilled people - would sack them when they found out and inform immigration, he said.
Other employers may be so short of labour they would train migrant workers up, McClymont said, but recoup the extra costs and higher wages from their staff.
"It's phenomenal the quality of the people that are coming in on these work visas at the moment - people who have no experience, they're completely illiterate, they just have no qualifications," McClymont said.
"They are the definition of unskilled but simply because they're being paid at a higher pay rate - they're being paid at median wage as required - therefore they're deemed to be skilled.
"That's the problem with INZ using this definition of skill based on pay rates, trying to achieve something through these high pay rates. It just encourages more and more wage recycling, which is exploitation, which is supposed to be the cornerstone of this government's immigration policy - that it stamp out exploitation."
The whole policy was a driver of exploitation, he said, and the government had been warned what would happen if it went down this route.
The Council of Trade Unions said it was among those submitters who had told the government to instead introduce open work visas.
Its secretary Melissa Ansell-Bridges said migrants were especially necessary in the cyclone recovery period and must be protected.
"The workers that we're bringing in absolutely have to be treated with with dignity and be coming here to do good work and so any sort of exploitative situation like that is very concerning.
"And there's that tension, that pressure, between needing to move quickly but needing to make sure that adequate checks and balances are in place so that we can avoid those kinds of exploitative situations."
In a statement Immigration New Zealand said it believed in most cases the employer was best placed to know who they were recruiting and how skilled or qualified they were.
"Under AEWV this includes having the qualifications, work experience, skills and other specifications listed by the employer, or meeting the requirements specified for the occupation if the occupation is on the Green List," INZ general manager Richard Owen said.
"We check during the visa application stage that the applicant has the qualifications or work experience required for the role. If an employer has advised us that a role doesn't require any qualifications or experience, then that would be taken into consideration as well.
"If a migrant worker appears not to have the skills and experience we'd expect for someone working in the role, this could indicate that the job is not genuine. Checks on genuineness of the job can happen both at application stage (job check and visa), but also post-decision as part of post-accreditation checks."
Those checks could include financial statements to demonstrate business viability, evidence of PAYE payments to migrant workers and evidence of how offshore recruitment agents of their migrant employees were paid.
INZ was aware of two allegations of payments of premiums being paid to accredited employers but could not comment further on those cases, he said.
"Charging premiums for employment is a breach of accreditation requirements, and, if substantiated, will result in the employer's accreditation being revoked. We take allegations of fraud seriously, and we encourage anyone who knows of similar offending to report it immediately.
"Investigations are considered on a case-by-case basis, and if it was found that visas, under this or any category, were granted based on incorrect information submitted to INZ, employers risk losing their accreditation, having their accreditation declined or being prosecuted under the Immigration Act 2009. Individuals could also face deportation."