Mr Howlin was speaking at the launch of a Labour bill aimed at delivering wage equality between men and women.
But when asked, he said it would be beneficial if all companies, public and private sector, published figures, saying people should have nothing to hide.
“Yes, it should all be known. It would be useful if they did. In the UK, we have seen a shareholder revolt demanding transparency in relation to executive pay. I don’t think has anything to be afraid of. If people are paid extraordinary high salaries there should be a reasoned argument as to why they were,” Mr Howlin said.
The proposed bill aims to close the earnings gap between men and women in Ireland was debated in the Seanad last night and is not being opposed by the Government.
Under the terms of the Gender Pay Gap Information Bill 2017, medium to large-sized companies would be required to regularly publish wage transparency surveys that would highlight any difference in pay between their male and female workers.
Mr Howlin added: “Equality and fairness have always been at the core of the Labour Party ethos, and while Ireland has come a long way on this front, women are still on an unequal footing in the workplace.”
He said that by requiring companies of 50 or more staff to regularly report on their pay scales, Labour’s Bill, which is based on legislation in other EU countries, will help to drive down any gender-based wage discrepancies. It’s not enough to simply hope that organisations will volunteer this information, Mr Howlin said.
At present rates, it would take up to 170 years before the gender pay gap is fully closed, he said.
“We in Labour believe that Irish women, and Irish society, cannot afford to wait that long, and we call on the Government to support this important and progressive legislation,” said Mr Howlin.
Senator Ivana Bacik told reporters: “Women here currently earn around 13.9% less than men –that figure equates to women in full-time employment working for free in Ireland for about one month of every year.”
“We passed equal pay legislation in Ireland more than 40 years ago, in 1974, and yet women have still not achieved anything close to pay parity with our male colleagues,” she added.
“Despite positive moves towards greater gender equality generally, the rate of change in pay levels has become stagnant — over the past 11 years, the gender pay gap has narrowed by only four percentage points.”