The Shareholders Association says a lack of awareness of the law designed to protect whistleblowers may have prevented workers at failing finance companies from speaking up.
Chief Ombudsman Dame Beverley Wakem wants to investigate why so few people use the Protected Disclosures Act, which came into force in 2001 and is aimed at encouraging people to alert authorities about poor or corrupt practices at workplaces.
She says only about 10 to 12 people a year ring her office about the Act and and fewer still actually take the step of using it to reveal information.
Investors in finance companies are not covered by the Act but employees in such companies are.
Shareholders Association chairman John Hawkins says some employees did make internal complaints during the collapse of a number of finance companies but he does not know of any who used the Act.
Mr Hawkins says the problem may be that many people do not know the law exists, particularly those in the private sector.
He says public sector employees are more likely to know about the legislation because specific procedures are required in those organisations.
Dame Beverley says the law could have been used during the collapse of finance companies.
She says she can't understand why nobody used the legislation to raise concerns about safety practices at the Pike River mine, where, if someone had investigated, some of the dangerous practices might have surfaced before it was too late.
"You can only do that in this sort of exercise where somebody's willing to put their head above the parapet.
"But they'll only do that if ... they're confident they will be protected and that there won't be any retaliation or retributive measures taken against them."
Insufficient protection, says lawyer
Barrister Steven Price, who specialises in media law, says the legislation does not promise complainants anonymity, nor that their complaint will be investigated.
"For another thing, it doesn't allow them to go to MPs, it doesn't protect them if they go to the media.
"They basically have to blow the whistle inside the organisation or to another government authority that can then check it out."
The Office of the Ombudsman has updated its website to make it clearer how to raise a matter under the Protected Disclosures Act.