Conservative MPs have backed the new dual discrimination clause in the Equality Bill despite having supported an earlier motion to reject the whole Bill at its second reading.
Last week the government tabled an amendment to the Bill enabling employees to claim discrimination caused by a combination of two characteristics, such as race and gender.
Theresa May, the shadow secretary for work and pensions, told Personnel Today that while the Tories will support the addition of the new clause, they were concerned about the impact it could have on employers.
She said: "We support the measures to tackle dual discrimination in the Equality Bill. However, there are legitimate concerns about how easy this will be to implement for businesses and we raised this issue in committee."
Mark Harper, Conservative MP for the Forest of Dean, warned a committee in the House of Commons on 2 July that the fear of more claims could cause employers to over-comply with discrimination legislation, for example by creating new equal opportunity monitoring systems.
Currently larger employers record gender ratios and the number of ethnic minority people they employ, which can be used as a defence at tribunals. But to defend against dual discrimination claims regarding both gender and race, employers could feel it necessary to overhaul these systems to record the number of ethnic minority women, which could prove costly.
Harper said: "The bigger problem, which was brought out in the British Chambers of Commerce response and has been touched on already by the Minister (solicitor general Vera Baird), is of employers gold-plating their practices."
In its response to the government consultation on the new clause, the BCC said: "If the government cannot communicate the change to businesses quickly and in an easy to understand way then businesses will over-comply, which will be an extra cost.
"This will be compounded by the fact that employers are even more nervous of falling foul of discrimination law, as compensation is uncapped and such claims can be very damaging to a firm's reputation."
The Equality Bill finished the committee stage in the House of Commons on Thursday and will now go through the report stage, before its third reading. The government hopes the Bill will be passed by the Commons and the Lords before the summer recess.
The solicitor general Vera Baird previously told Personnel Today she feared the Equality Bill would not become law if the Conservatives came to power at the next general election because of the party's opposition to the proposed legislation at its second reading.