The many economic inequalities between women and men are inevitably built into and easily magnified by tax laws. It can be difficult to see how tax laws themselves can be sources of sex discrimination, but no matter how gender neutral tax laws may be, they are almost never completely gender-equal.
In recent years in Canada, it has become very obvious that tax laws play a big role in intensifying the concentration of after-tax incomes and wealth in the hands of the most economically-powerful and thus politically-powerful actors in any given country. Because little of this data on ‘top 1%’ incomes has been presented with breakdowns between women and men, it is hard to see that in fact, a significant majority of those with the smallest incomes are women – it is men’s high incomes that are growing so quickly.
This paper by Queen's University Law Professor Kathleen Lahey goes into technical detail of how that plays out