Many Americans would no doubt be surprised to learn that in much of the nation their fellow citizens can be fired from their jobs for being lesbian, gay, bisexual or transgender. In fact, 29 states have no explicit protections against employment discrimination on the basis of sexual orientation or identity -- and there is no federal law extending that protection, either.

But there could be. In the Senate this week, Democrat Jeff Merkley of Oregon is introducing the Employment Non-Discrimination Act to prohibit intentional employment discrimination against LGBT workers by employers, employment agencies and labor unions. Similar legislation is being introduced in the House.

The Civil Rights Act of 1964 prohibits employment discrimination on the basis of race, color, religion, sex or national origin. The act is mute on discrimination based on sexual orientation or identity.

It’s clear that such discrimination takes place. According to a 2011 report by the Williams Institute at the University of California at Los Angeles School of Law, “During the past four decades a large body of research using a variety of methodologies has consistently documented high levels of discrimination against lesbians, gay men, bisexuals and transgender people at work.” Anecdotal evidence is also readily available.

In the last Congress, 43 senators co-sponsored legislation to end LGBT employment discrimination. The law would hardly be a burden. The overwhelming majority of Fortune 500 companies already subscribe to its guidelines. So do many municipalities. Private clubs, religious organizations and businesses with fewer than 15 employees would be exempt.

The tidal change in public attitudes toward same-sex marriage -- nine states and the District of Columbia have legalized same-sex marriage, which is being deliberated by the Supreme Court -- only underscores the obvious: This legislation is long overdue.

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