On the eve of Equal Pay Day, celebrated this year on April 2, House Democrats passed a new law intended to help close the wage gap between men and women.

The Paycheck Fairness Act aims to strengthen equal pay protections for women by expanding upon the Equal Pay Act of 1963 and the Fair Labor Standards Act. It would ban employers from asking job applicants how much they previously made, prohibit companies from retaliating against workers who share wage information, and increase penalties for equal pay violations.

Under this bill, companies would need to share with the Department of Labor how much they're paying employees and demonstrate that any salary differences are based on factors other than sex, such as education or experience. Finally, the legislation would fund additional training for Equal Employment Opportunity Commission staff to better identify and handle wage disputes.

House Speaker Nancy Pelosi and Democratic lawmakers reintroduced the Paycheck Fairness Act on Jan. 30 — the bill's author, Rep. Rosa DeLauro (D-CT), first introduced it in 1997. It went up for a final vote on March 27, passing 242-187. Seven Republican representatives were among those in favor.

But to become law, the bill must now pass in the Senate, where it faces an uphill battle it already lost once. The Paycheck Fairness Act previously passed the House back in 2008 and 2009, when Democrats were then in the majority, but failed in the Senate the following year. Since then it's struggled to gain momentum in either chamber.

However, Democrats believe the timing is ripe now for such legal change, thanks to the #MeToo movement and the historic number of women currently serving in Congress.

"This is historic. Rosa has been introducing this bill forever," House Speaker Nancy Pelosi told the House Democratic Caucus on Tuesday, according to Vox. "But public sentiment — public, social media, and all the rest — with help us with this."

When Pelosi reintroduced the bill earlier this year she said she hoped President Trump would sign off on it by Equal Pay Day, but such ambitions may be overly optimistic. Senate Majority Leader Mitch McConnell (R-Ky.) is unlikely to allow members to even vote on it, having previously called the act "just another Democratic idea that threatens to hurt the very people that it claims to help."

Since 2012, the GOP has voted at least four times to block the legislation from consideration, arguing that it would discourage businesses from hiring women because of the extra transparency and compliance measures it mandates and make it too easy for workers to take firms to court over pay inequality allegations. Republicans have also stated that the bill is unnecessary because gender discrimination is already illegal.

While the practice may be illegal, men continue to out-earn women, often for performing the same work. Women in the U.S. will earn 79 cents for every dollar men earn in 2019, or about 21.4 percent less, according to a new analysis conducted by Glassdoor of more than 425,000 U.S. employees' salaries.

Even when Glassdoor compared workers who hold the same job title and have similar educational backgrounds, work experiences, office locations, and employers, men received higher salaries for doing the same work — about 5 percent more, annually.

And a recent study from the Harvard Business Review found that when legislation requires companies to disclose gender pay disparities, the gender wage gap shrinks and more women are hired and promoted to senior roles. (The study also notes, however, that pay didn't become more equitable because women's wages rose, rather male wage growth slowed.)

"At its core, this bill is about a simple principle: Women and men working in the same job deserve the same pay, DeLauro said after the House Education and Labor Committee voted in support of the act. "Equal pay is a matter of right and wrong, and pay discrimination is unacceptable. It is critical for working families, and we all diminished when we fall short."

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