ROBERT SIEGEL, HOST:
There's a thing that sometimes happens when you apply for a new job. You submit your resume. The interview goes well. And then the company asks, how much are you making in your current job? Well, states have started passing laws that ban companies from asking that question. California's law went into effect this week. Noel King from our Planet Money team looked into the history of this expanding legal trend.
NOEL KING, BYLINE: Here's what I've always wondered - if a company asks, how much do you make at your current job, why not just lie, tack 20 grand onto your salary? I asked Emily Martin of the National Women's Law Center.
EMILY MARTIN: So it's possible that a company could seek to confirm that information with your employer. And certainly if the new job found you had lied could take that into account and think, I actually don't want to - I want to rescind this offer because this applicant has shown herself to be untrustworthy.
KING: OK, that is the public service portion of this story. Don't lie. You might get caught. The reason I called the National Women's Law Center is that this push to ban the salary question is part of the fight for equal pay. Here's what supporters say - asking women about their previous salaries gets them stuck making lower wages than men because they are often already making less than men. We know that. And if a new salary is based on a previous salary...
MARTIN: It's one way in which the wage gap follows women and grows over time.
KING: There's been an idea around for a long time to stop this - just don't let companies ask how much you're making. In Massachusetts in the mid-'90s, a woman named Ellen Story thought this should be a law. She'd recently been elected to the Statehouse. It was a big change from her town, Amherst.
ELLEN STORY: Amherst, you know, everybody wears blue jeans and Birkenstocks. The Statehouse is very formal. I almost always wore a suit. So I was very conscious of dressing the part.
KING: And she was very consciously trying to get this law passed. She and a co-sponsor started reaching out across the aisle, getting local business leaders on board. But she says some business groups like the National Chamber of Commerce didn't like the idea. They couldn't really say it publicly.
STORY: I mean, you would just look like a fool if you said men always do a better job than women, so they have to be paid more. You know, that's just so blatantly untrue.
KING: So they just said, we don't want politicians making rules on how and who we hire. So the bill got stuck in committee, where it stayed for nearly 20 years. Ellen kept it up. She got the Greater Boston Chamber of Commerce on her side. And after years of this, she and her allies in the Statehouse got the speaker to put it up for a vote.
STORY: If the speaker of the House had not been in favor of this it would never have come to the floor.
KING: And who was the speaker? How did you get him or her on your side?
STORY: Well, of course it's a him.
KING: The answer, of course - she persisted. And times were changing. There were more women in the legislature. Hillary Clinton had run for president. In August 2016, the Massachusetts bill finally passed into law. And then other states followed - New York, Delaware, Oregon, also Puerto Rico. Just this week, California's law went into effect, and there's a good chance it won't be the last. Noel King, NPR News.
SIEGEL: Noel King is with our Planet Money team. And you can hear more stories like that one on NPR's newest daily podcast, The Indicator. They take a number or a phrase from the news and they find the big idea behind it. That's The Indicator from Planet Money.
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