Imagine a job application that asks an applicant to disclose how much she currently makes. If the salary turns out to be significantly less than what the company was prepared to offer, an employer might try to get away with paying a lower wage. That could put the applicant at a disadvantage and lead to a lower salary offer.

In Massachusetts, that kind of scenario could soon be a thing of the past. A new bill signed this week by Republican Governor Charlie Baker promotes equal pay for men and women doing substantially similar work. To promote fair pay, the law prevents employers from requiring applicants to disclose salary history “as a condition of being interviewed, or as a condition of continuing to be considered for an offer of employment.”

That could prove particularly significant for women. Women earn less than men on average. If a woman is paid less than a man for comparable work, and her salary is used by future employers as a baseline to determine what she will be paid in subsequent jobs, that financial shortfall may be more likely to persist over the course of her career.

“Women can be tethered to past salaries in a way that cements lower wages in place,” said Jocelyn Frye, a senior fellow at the Center for American Progress, a progressive think tank. “This bill tries to eliminate that problem and get employers to think about what an equitable salary is for the job based on the value of the job, not what someone made in the past.”

The Massachusetts law is set apart from other existing pay-equity legislation: Supporters of the legislation are calling the ban on employers asking applicants about salary history “a first-in-the-nation provision.” After the legislation passed, the Center for American Progress heralded it as “one of the strongest equal-pay bills in the nation.”

The law won’t be a panacea. Wage disparity between men and women is the result of a complex set of factors.  And even if an employer can’t compel job applicants to reveal how much they earned in a previous job prior to making an offer, that alone won’t necessarily eliminate wage discrimination.

To ensure equal pay, the legislation includes a number of other provisions. It promotes pay transparency by making it illegal for an employer to prevent employees from talking about how much money they make. It clarifies that a job title or job description alone does not determine whether work can be considered comparable. It also encourages employers to proactively take steps to eliminate wage discrimination on the basis of gender.

The law says there are legitimate reasons for variation in wages based on factors such as seniority, education, and experience. However, it states that “time spent on leave due to a pregnancy-related condition and protected parental, family, and medical leave shall not reduce seniority.” In other words, women cannot be penalized in terms of workplace seniority for taking pregnancy or family leave.

“That’s really key,” said Fatima Goss Graves of the National Women’s Law Center. “There’s an overall wage gap, but there’s an even larger wage gap for mothers. Women can end up having lower pay and fewer benefits because of their disproportionate role as caregivers or the time they take for family leave. So to be able to sort of name that and propose a solution in law is important.”

The legislation faced opposition from some businesses. As Mark Gallagher of the Massachusetts High Technology Council told The Boston Globe in July, “The council cannot support legislation that would create a presumption that any pay differential between employees of different genders is the result of discriminatory action by an employer.”  In the end, though, the Massachusetts House and Senate unanimously approved the legislation.

State-level efforts to eliminate gender discrimination in the workplace are moving forward as gridlock prevails in the U.S. Congress. At the federal level, Republicans have blocked the Paycheck Fairness Act, a law intended to build on the Equal Pay Act of 1963. And yet, at the state level, Republicans and Democrats alike have gotten behind equal pay legislation. While recent laws strengthening protections for women in the workplace in California and New York were enacted by Democratic governors, the Massachusetts law was approved by a Republican governor.

Advocates of pay equity argue that these state actions make a case for further federal protections. “Enacting these kinds of state laws shows that the world doesn’t collapse when we create additional protections against gender discrimination in the workplace, which is often the argument from opponents at the national level,” said Ariane Hegewisch, the program director for employment and earnings at the Institute for Women’s Policy Research.

The passage of new pay-equity legislation at the state level, and in particular the implementation of policy not seen elsewhere in the U.S., could create case studies that help determine what works and what doesn’t. This might serve as a template for future legislation. Whether the Massachusetts law is effective or not, it should offer hard evidence of the consequences of pay-equity legislation—and that, in itself, is a benefit.