Gender bias is a preference or prejudice toward one gender over the other. Bias can be conscious or unconscious, and may manifest in many ways, both subtle and obvious. In many countries, eliminating gender bias is the basis of many laws, including those that govern workplaces, family courts, and even the voting booth. Despite these efforts, many legal and political scholars argue that total gender parity remains a far off goal, one which many region are not remotely close to reaching. The legality of gender bias is an area of huge contention in regard to pay equity between the sexes. Historically in many countries, men make more money over a career than women, even if they hold the same job. While the disparity has dwindled since the mid-20th century, it still exists in most areas to some degree. Opponents of additional laws increasing protection of women's equal pay argue that this may be due to women working less over their lives, instead making a choice to remain at home and raise children. Women's rights activists often cite this argument as part of the overall gender bias of modern society, suggesting that women are financially punished for choosing to rear children, despite the fact that this action is vital to thecontinuance of the state. It is also important to remember when considering gender bias and the law, that not all regions approve or desire gender equality under the law. In some countries, women are not allowed to drive, let alone vote. Studies of some regions have also showed tremendous gender bias in laws, with women being subject to severe penalties, including execution, for crimes such as adultery, whereas for men, adultery may not be considered a crime at all or may have lighter sentencing guides.