Women would get information about pay rates in their workplace to test if there is gender-based discrimination, under new legislation welcomed by the Human Rights Commission.
A private member's bill by Green Party MP Jan Logie has been drawn from the ballot.
It would make all employers include gender when recording information about pay rates for different roles in their workplace.
Employers would be required to pass that information on to the Department of Labour for publication in aggregate form.
The law change would also enable any employee to demand their employer provide "aggregated data showing the pay and gender for all employees doing the same kind of work".
"We don't know if you are being paid the same as the person next to you doing the same job or not," Logie said. "At the moment women only find out by accident, if at all, if they're being paid less than a male colleague."
Logie said how much an individual earned would be private as the data would be released in aggregate form.
However, in some workplaces the small number of similar roles could create privacy issues.
In these situations, Logie said the information would be given to an independent reviewer.
"That independent reviewer would say, 'Actually, there is a problem here and it should be addressed'. And you can go and take that to the Employment Court."
Asked if an outcome of that independent review could include the salaries of the people involved being disclosed, Logie said that detail would need to be worked out.
"I don't think it would require them to tell them the pay rate. But it could be sorted out through the court. And, actually, if we want to make sure there is equal pay then you are going to find out when you get the extra money in your paypacket."
The Human Rights Commission welcomed Logie's bill. Equal Employment Opportunities Commissioner Dr Jackie Blue said it was timely, given the current debate taking place on pay equity.
"The Commission has been calling for greater pay transparency for some time and urging New Zealand to follow in the steps of countries like the UK, where from 2018, businesses with over 250 employees must disclose what they are paying in salaries and bonuses to their male and female staff.
"We have already seen great leadership from the State Services Commission in publishing the gender pay gap data of public service departments. With this Bill, private businesses will be required to have greater pay transparency as well."
Few Opposition MP bills make it into law but their selection allows the issue to be debated in a first reading.
Two other member's bills were drawn today from the ballot. Labour MP David Parker's Ombudsmen (Cost Recovery) Amendment Bill would enable the Ombudsman to fine government departments for delays and breaches of the Official Information Act (OIA).
Media can lodge OIA requests with government departments, asking for documents, emails and other information. If information is released it must be done so within a maximum of 20 business days, unless an extension is required.
Parker said presently delays and breaches of the OIA could not be effectively policed.
"This bill, if passed, will allow media to access what they need to keep politicians, public officials and government departments to account."
Labour MP Ruth Dyson's Crown Minerals (Protecting World Heritage Sites) Amendment Bill was also drawn today.