California state Sen. Hannah-Beth Jackson speaks at a “Families Belong Together” event on June 30 in Oxnard.

Juan Carlo/Ventura County Star/USA TODAY Network

Beginning next year, California's corporate board rooms will be required to take on a different look.

Gov. Jerry Brown on Sunday signed landmark legislation that will require all publicly traded companies with headquarters in California to have at least one woman on their board of directors by the end of 2019. The minimum requisite will increase to two by the end of 2021.

No other state has passed similar legislation, although a handful have approved nonbinding resolutions with a similar aim of gender equality.

Though Brown expressed some misgivings about the law, which has been criticized as governmental intrusion into private business, he saw more pros than cons in its passage.

More: Gender quotas: California ponders breakthrough bill to boost female executives

“There have been numerous objections to this bill and serious legal concerns have been raised,’’ Brown said in a statement. “I don’t minimize the potential flaws that indeed may prove fatal to its ultimate implementation. Nevertheless, recent events in Washington, D.C. – and beyond – make it crystal clear that many are not getting the message.’’

Brown's comments appeared to reference last week's Senate hearings involving Supreme Court nominee Brett Kavanaugh and Christine Blasey Ford, who has accused him of sexual assault when both were teenagers.

The FBI has since opened a background investigation on Kavanaugh, at the request of the Senate Judiciary Committee.

Though several studies have shown companies with at least one female director perform better than their all-male counterparts, progress toward gender equality in the boardroom has been a slow slog at best.

State Sen. Hannah-Beth Jackson, a Democrat from Santa Barbara who co-authored the bill, pointed out the percentage of women in California corporate boards had barely nudged up from 15.5 percent in 2013 to 16 percent this year.

The bill provided statistics from 2017 showing one-fourth of California’s public companies in the comprehensive Russell 3000 index had no female directors. Nationally, nearly half the 75 largest IPOs from 2014-16 were launched by companies with no women on their boards.

“I think this is a giant step forward not just for women but also for our businesses and our economy,’’ Jackson told USA TODAY. “It’s a win-win-win.’’

Jackson said she’s optimistic other states will follow California’s lead in the same way the equal-pay bill she authored in 2015 became a template for similar legislation in most of the country.

However, Jackson acknowledged this legislation is likely to face legal challenges. The California Chamber of Commerce staunchly opposed the bill and questioned its state and federal constitutionality.

“It’s my hope that corporations, rather than fight this, will acknowledge its value and take the lead on pulling together and bringing greater diversity into their boardrooms,’’ Jackson said.

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