A gay-rights flag outside the U.S. Supreme Court. Credit: Diego M. Radzinschi / NLJ

Familiar dividing lines are taking shape in a new federal appeals court case from Missouri that confronts the scope of workplace protections for gay, lesbian and bisexual workers.

Major U.S. companies including Microsoft Corp., Airbnb Inc., eBay Inc., and Viacom Inc. are backing the worker, a health care specialist named Mark Horton who sued St. Louis-based Midwest Geriatric Management for allegedly pulling his job offer when they discovered he is gay.

Meanwhile, conservative states lined up against liberal-leaning states, and the U.S. Equal Employment Opportunity Commission threw its support to Horton, whose case is pending in the U.S. Court of Appeals for the Eighth Circuit. Horton lost in the trial court.

Horton's case tackles a question that has divided other courts and been left unresolved by the U.S. Supreme Court: whether sexual orientation should be considered sex discrimination under federal civil rights laws.

The Supreme Court has two petitions that tee up that question. The most recent ruling, from the en banc Second Circuit, said Title VII of the federal Civil Rights Act does shield gay and lesbian workers from discrimination.

In Horton's case, friend-of-the-court briefs have piled up in recent weeks. What follows is a snapshot of some of the arguments being made.

>>> Big business: A coalition of 47 companies and organizations—many representing the tech, retail and financial sectors—”support the notion that no one should be passed over for a job, paid less, fired, or subject to harassment or any other form of discrimination based on nothing more than their sexual orientation, which is inherently sex-based.” The companies on the brief are represented by Quinn Emanuel Urquhart & Sullivan and the Missouri firm Klar, Izsak & Stenger. The brief, mirroring others that have been filed in federal appeals cases, argued that excluding gay workers from Title VII protections, “has wide-ranging, negative consequences for businesses, their employees, and the U.S. economy.”

>>> EEOC: The EEOC's arguments are not novel, but they incorporate some of the newest appeals court rulings that have tested the scope of LGBT protections. The agency's brief pointed to the Second Circuit's ruling in Zarda v. Altitude Express, where the full court ruled against the company. Lawyers for the company have petitioned the Supreme Court. “An employer cannot identify an employee as gay or lesbian, and therefore cannot engage in sexual orientation discrimination, without considering that employee's sex in relation to the sex of the persons to whom the employee is attracted,” EEOC lawyers wrote. Also from the brief: “Imagine an employer that receives identical emails from Mark Horton, a male writing about his male partner, and 'Mary' Horton, a female writing about her male partner. The employer rescinds Mark's job offer but not Mary's. In this scenario, only the employee's sex has changed, but this one change makes all the difference to the employer. Thus, the employer's conduct fails the Supreme Court's 'simple' test for sex discrimination: 'whether the evidence shows 'treatment of a person in a manner which but for that person's sex would be different.'” An open question in Horton's case is whether the U.S. Justice Department, which lined up against the EEOC in the Second Circuit, will take a stand.

>>> Conservative states: Arkansas, Louisiana, Michigan, Missouri, Nebraska, Oklahoma, South Dakota and Texas jointly filed a brief supporting Midwest Geriatric Management, represented by the St. Louis firm Lewis & Rice. “From 1964 until very recently, Title VII's prohibition of discrimination based on 'sex' was understood by all to mean discrimination based on whether an employee is biologically male or female,” lawyers for the states said in their amicus brief. “Despite numerous attempts by litigants to expand the scope of Title VII to include discrimination based on sexual orientation, the Courts of Appeals were uniform in limiting the statute to its original meaning. Congress, aware of these rulings, has declined on numerous occasions to amend Title VII to cover sexual orientation discrimination.” The states said they “have an interest in ensuring that the federal judiciary does not usurp the prerogatives of the judicial branch by overturning decades of settled understanding of the meaning of federal law, especially when that meaning has been repeatedly ratified by Congress.”

>>> Liberal states: The District of Columbia and 15 states—including California, Connecticut, Illinois, Maryland, Massachusetts, New Jersey, and New York—urged the Eighth circuit panel to embrace the Second and Seventh circuits, which both recognized anti-discrimination protections under Title VII for gay and lesbian workers. “Recognizing the significant harms that result from such discrimination, many of the Amici States have enacted laws to prohibit sexual orientation discrimination in the workplace,” lawyers for the states wrote in their brief. The attorneys wrote in the brief: “The Supreme Court has routinely recognized that, to effectuate the remedial purposes of Title VII, the statute's reach includes conduct that was not always recognized as falling within its scope, such as sexual harassment and gender stereotyping claim.”

Read more:

New Petition at SCOTUS Confronts Scope of LGBT Workplace Protections

EEOC Takes 'Zarda' LGBT Win on the Road to Another US Appeals Court

US Appeals Court Ruling Highlights 'Evolving Nature' of Title VII Protections

How PwC Handled Its First Transgender Employee Transition in the Workplace

Trump's EEOC General Counsel Pick Wants New Focus on Individual Cases, Not Systemic

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