Members of GetEQUAL, a lesbian, gay, bisexual and transgender organization, stage a protest on Capitol Hill May 20, 2010 in Washington, DC. (Photo by Alex Wong/Getty Images)

On Monday, the Senate voted to formally begin deliberations on the Employment Non-Discrimination Act, or ENDA, marking a big step for a potentially historic piece of legislation.

The legislation, which would ban discrimination based on sexual orientation or gender identity in the workplace, is reportedly expected to pass the Senate this week, but that hardly means it will become federal law—or even see the floor of the House. Speaker John Boehner reiterated his opposition on Monday and aides have said he would not bring it up for a vote, despite recent polls showing that more than 7 in 10 Americans favor protecting lesbian, gay, bisexual and transgender employees from job discrimination.

But let's suppose for a moment that the bill does pass the Senate (which seems likely), manages to get onto the House floor and receives the votes to pass (an outcome with far longer odds). Hypothetically, what would that mean for leaders in the workplace?

In many cases, very little. Discrimination based on sexual orientation is already banned in 21 states plus the District of Columbia; 18 of those states and D.C. also protect against gender identity discrimination. Almost 97 percent of the 2012 Fortune 500 companies specifically include such protections in their workplace policies. And many other firms elect themselves to ban discrimination against LGBT employees, even where it's not expressly prohibited by law. Says Garry Mathiason, the chairman of global employment law firm Littler Mendelson, "if it’s a multi-state company, it would be very common that they would already cover that protection."

Moreover, legal experts say, there's unlikely to be a floodgate of claims if the ban does go into place. Katharine Parker, a partner at Proskauer who co-leads the law firm's employment counseling and training group in New York, points to research done by the New York City Bar's Labor and Employment Committee. It found that after New York amended its laws to prohibit sexual orientation and gender identity discrimination, these types of complaints comprised less than 1 percent of those filed with the city's Commission on Human Rights between 2003 and 2010. "I don't anticipate a huge uptick in litigation resulting from the passage of ENDA," she wrote in an e-mail.

Mathiason agrees: "I don't expect an avalanche of claims," he says. "I don’t think it’s that controversial and I don’t think it’s going to be a sea change at this point. We've already passed that point." A July report from the Government Accountability Office report also showed relatively few employment sexual orientation and gender identity discrimination complaints in the states that had passed such bans.

If ENDA does eventually become federal law—and that's still a big if—lawyers advise organizations to update their training along with their policies. If an employer updates its policy but doesn't do any training to go along with it, "there could be a claim that you haven’t done what’s required to maintain an anti-discrimination environment," Mathiason says. Leaders may think their workplace has the sort of culture where such discrimination doesn't exist, but according to recent Pew research, 21 percent of LGBT adults surveyed say they have experienced it on the job.

Jena McGregor is a columnist for On Leadership.

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