Interesting scenario @peterma - clearly she has a contract of employment and provided her decision to take this passive aggressive step falls within the wording of that contract, she is entitled to take it.
If not, she is breach of her employment conditions and would rightfully receive a written warning.
However the likelihood is that this would be taken as an opportunity to claim “Constructive dismissal” and instigate a tribunal event. She would likely get some recompense from the tribunal, although it is a long time since I went to one, they may decide that her action was partly to blame and reduce the award.
Naturally, this would prejudivce any future potential employer against treating her as “an equal” with someone who had never taken an employer to tribunal.
As a Freelance QS, I used to charge a slightly bigger hourly rate than PAYE employees get, because I have to cover “Sickness, holidays, NI”, etc etc.If I were a young female “freelance” I would need to decide whether I needed to charge a little more still, to cover “Maternity” requirement.
The likelihood is that I woud decide not to be “Self-employed” in this case and that I would get a “nice secure job” somwhere that the Employer would be forced to cover the costs of My decisions to have children.
However, it is currently illegal for that Employer to pay “more reliable” (male) employees a premium for this, so I see many smaller Offices and firms, with somwhat older females working within them.
Now life has reached a stage where I can relax a little and can now reduce my prices and take on a different type of clients; small builders, subcontractors and clients who feel they are being “abused” because they cannot afford a full-time QS. Generally I’ll charge them a fairly nominal amount to look through the documents, discuss the issues and form an opinion as to whether I can help them in a cost effective way or not. If the answer is in the affirmative, I’ll put together the claim for them, work out their Final Accounts" or whatever, write the correspondence and hopefully get them their money (Often considerably More than they thought they were due ! )
I am still as good as I was, but am happy to work for less and they get the advantage of my skills and abilities at a discount rate.
My prima facie opinion is that your “young lady” is playing a dangerous and as I said “Passive-Aggressive” game by taking her apparent actions - but of course I don’t know the full facts.
She already is disadvantaged by the perceived “threat” of “maternity absence” from getting an equal job in the private sector and if she is revealed to future “Employers” as a “trouble - maker” is liable to be offerred only second rate opportunities if any !
My advice to her would be to get the “better paid” job and leave, on the basis that if that was all the Employer thought she was worth, they were wrong. I would Not advise her to demand “Equal pay” or to take the action she has.
It could be worth her asking for a pay rise and pointing out her value to the firm, but unilaterally going “Part-time” (whilst I can see her Anger being assuaged by th eaction), cannot but harm her current credibility by casting doubt on her “commitment” and her future prospects as explained above.