Senator Elizabeth Warren (D-MA), alleged champion of equal pay, has some explaining to do.

According to The Washington Free Beacon:

...women working for [Senator] Warren were paid just 71 cents for every dollar paid to men during the 2016 fiscal year...The median annual earnings for women staffers, $52,750, was more than $20,000 less than the median annual earnings for men, $73,750, according to the analysis of publicly available Senate data. 

When calculated using average salaries rather than median, the pay gap expands to just over $26,051, or about 31 percent.

As one of the most vocal proponents of equal pay legislation, why would Senator Warren allow her female staffers to be paid significantly less than their male counterparts? It simply doesn't make sense - unless Warren knows that the wage gap is not about discrimination, and is in fact due to a large number of other factors.

The "77 cent wage gap" statistic propagated by politicians from Elizabeth Warren to President Obama has been debunked multiple times. One of the most compact yet comprehensive analyses comes from Sarah Ketterer, who writes in The Wall Street Journal:

...a closer look reveals a different picture. The Bureau of Labor Statistics (BLS) notes that its analysis of wages by gender does “not control for many factors that can be significant in explaining earnings differences.”

What factors? Start with hours worked. Full-time employment is technically defined as more than 35 hours. This raises an obvious problem: A simple side-by-side comparison of all men and all women includes people who work 35 hours a week, and others who work 45. Men are significantly more likely than women to work longer hours, according to the BLS. And if we compare only people who work 40 hours a week, BLS data show that women then earn on average 90 cents for every dollar earned by men.

Career choice is another factor. Research in 2013 by Anthony Carnevale, a Georgetown University economist, shows that women flock to college majors that lead to lower-paying careers. Of the 10 lowest-paying majors—such as “drama and theater arts” and “counseling psychology”—only one, “theology and religious vocations,” is majority male.

Conversely, of the 10 highest-paying majors—including “mathematics and computer science” and “petroleum engineering”—only one, “pharmacy sciences and administration,” is majority female. Eight of the remaining nine are more than 70% male.

Other factors that account for earnings differences include marriage and children, both of which cause many women to leave the workforce for years. June O’Neill, former director of the Congressional Budget Office, concluded in a 2005 study that “there is no gender gap in wages among men and women with similar family roles.” Time magazine reported in 2010 that in 98% of America’s largest 150 cities, including my hometown of Los Angeles, single women under 30 actually earned, on average, 8% more than their male counterparts.

Ms. O’Neill and her husband concluded in their 2012 book, “The Declining Importance of Race and Gender in the Labor Market,” that once all these factors are taken into account, very little of the pay differential between men and women is due to actual discrimination, which is “unlikely to account for a differential of more than 5 percent but may not be present at all."

In the following video, American Enterprise Institute (AEI) Fellow and self-declared feminist, Christian Hoff Sommers, brilliantly and succinctly explains the pernicious wage gap myth:

With full knowledge that the 77 cent wage gap statistic is wildly misleading, one must come to one of two conclusions regarding Senator Elizabeth Warren's repeated invoking of it in conjunction with her apparent refusal to acknowledge it among her own staff - either the senator is shockingly dull, or she is exploiting the myth for her own political benefit.

Which option seems more likely?

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