Could a new law - currently applied in Massachusetts, USA - that makes it illegal for employers to ask jobseekers their current salary prior to offering them a position work in the UK?

 I can see the benefit of the legislation below, in that it will put a stop to gender inequality when it comes to pay, I am concerned that candidates could use this to their advantage to leverage their salary way above their market value.  We tend to suggest a 10% uplift on base salary (obviously dependent upon the whole package) when considering an external move.   We have however witnessed candidates wanting as much as 50% as an uplift on their existing salary.   It doesn't matter how good a candidate is, it merely prices them out of the market long term.   So I am not sure this legislation would work in the UK job market.