New Zealand companies found guilty of corporate manslaughter should face heavier fines and the potential to be sued, a corporate law expert says.

Auckland University Commercial Law Professor Susan Watson said the  Accident Compensation Corporation (ACC) regime had led to a corporate environment where no one individual was ever held responsible and penalties were weak.

Heavier penalties would act as an incentive for companies to "grow a conscience" and take responsibility for workplace safety, she said.

In a major study into workplace safety, Watson's research found that New Zealand had twice the rate of workplace fatalities as Australia.

The serious injury statistics were "very high and worrying", she said. There were 41 work-related deaths reported to the Department of Labour in 2011.

A New Zealand company charged over a workplace fatality would face a maximum fine of $500,000 for a 'knowing' offence under current legislation.

An Australian company could be fined up to $3 million for the same offence.

Watson said there was no reason for corporations to improve safety levels because they couldn't be sued under New Zealand law for personal injury.

"Individuals are careful because, for most of us, hurting or killing someone is not something we want to carry around for the rest of our lives.

"However, the corporate entity itself has no conscience, no matter what individuals within the corporation think."

It was time for New Zealand to consider models in other countries where companies could be sued for personal injury, Watson said.

According to statistics compiled by Watson, the rate of workplace-related accidents increased during the period when ACC was introduced in the 1970s, while Australia's figures trended down.

"New Zealand's ACC is unique. It's what differentiates us from the rest of the world.

"But perhaps it also doesn't incentivise companies to work hard enough to ensure workplace safety is strictly adhered to."

Ministry of Business, Innovation and Employment Labour Group spokeswoman Rachel McQuillan said the ministry was unable to comment on whether heavier penalties would be effective.

The ministry had a number of tools it could use in terms of enforcement action which were proven to be effective, she said.

"We do believe that targeting high risk industries with information, education and compliance campaigns can have a positive effect on the work toll."

Three safety programmes, part of which focused on compliance, were being run as part of a plan targeting the five sectors with the highest incidence of workplace health and safety injuries.

- © Fairfax NZ News  16/8/2012