Company bosses are being advised they can press on with sexist dress codes - because workers cannot afford sky-high tribunal fees.
Many lawyers no longer advise that sexist dress codes - such as requiring high heels or short skirts - will land a company in court after the number of legal cases plummeted, an inquiry by MPs was told.
Earlier this year, actress Nicola Thorp hit the news after being sent home from her temp job after refusing to wear shoes with a two to four-inch heel.
Nicola's protest sparked a 150,000-signature petition calling for firms to be banned from demanding high heels be worn - and revelations that women are being forced to wear make-up and short skirts.
But, a Commons committee was told, rising tribunal fees mean some lawyers feel that a costly legal claim is unlikely to follow such an incident - Something that could be interpreted as a green light to sexist companies.
Harini Iyengar, a barrister specialising in employment discrimination, said: "The drop-off in employment litigation is now starting to affect the advice that we give to employers
"Where we might have said that, 'In my opinion, you may well be at risk of claims', now you have to think 'Can I properly write that?'.
"Instead, you have to write something like, 'It would be best practice if you did this and this' - rather than 'I need to advise you that you may well get sued'."
John Bowers QC, of Littleton Chambers, added: "They take a punt on the idea that nobody is going to bring a claim."
The situation was condemned by Labour MP Catherine McKinnell who said: "It seems employers are being advised they can get away with things they wouldn't have done before.
"This risks putting staff - and particularly female workers - in a position that is really not acceptable in 21st century Britain."
It costs as much as £1,200 to bring a claim to an employment tribunal after fees were introduced in 2013 - triggering a drop of almost 70 per cent in the number of cases.
Nicola Thorp hit the headlines after being told to leave PwC's outsourced reception firm Portico on her first day when she refused to wear high heels.
The Commons petitions committee launched an inquiry into the issue to gather evidence ahead of a likely debate on the 27-year-old's petition, in the autumn.
The MPs already have evidence that high heels are costing British businesses £260 million a year because women take sick leave for the health problems they cause.
Ruth Campion said she was made to feel like a "prostitute" by British Airways after being forced to wear high heels and make-up to look 'sexy'.
And sales assistant Emma Birkett gave evidence that she was told to "wear shorter skirts and unbutton a blouse a little".
On clothing requirements, Mr Bowers added: "The problem is the introduction of fees for employment tribunals - because these are the sort of cases which are among those not being brought.
"Even if you won a case like this, the award is likely to be £250 - or maybe £1,000 - and you are being told that you've got to run up a bill of several hundred pounds."
Ms Iyengar also said firms were unwilling to spend money on "being a best practice employer" when their rivals were not.