Equal political representation and an equal share of women in parliaments and the executives is obviously a human rights issue. In a representative democracy, one can reasonably expect to have a parliament that is roughly representative of the population in general: poor people should have their representatives or delegates just like rich people, women just like men, minorities just like majorities. This “representativity” or “representativeness” isn’t an absolute requirement. One can have a democracy without it. The people, after all, may decide that their views are best represented by an all-male, all-white body of parliamentarians for example.
However, it seems statistically unlikely that this would be their decision in each consecutive election in each democratic country. Imbalances in the demographics of parliament that persist over time and space are probably not the result of the choices of voters but of other factors, such as discrimination, unequal opportunities etc. If that’s the case, we are dealing with an imperfect democracy because democracy means equal influence and an equal chance to get elected (art. 21 of the Universal Declaration and art. 25 of the International Covenant on Civil and Political Rights).
And that seems to be the case. Some people, therefore, propose “pink quotas” which impose minimum numbers of female representatives (something like affirmative action or positive discrimination). I’ll discuss the desirability of such quotas another time.