O'Daniel's claims of retaliation presented the appeals court a fresh chance to address the scope of Title VII employment rights, which forbid companies from discriminating on the basis of sex, race, color, religion and national origin. Courts, however, are divided over whether the law extends to protect against sexual orientation bias.

At Wednesday's hearing, Fifth Circuit Judge Catharina Haynes seemed disinclined to reach the divisive question about the scope of Title VII, an issue that is pending in petitions at the U.S. Supreme Court. Haynes zeroed in several times on the substance of O'Daniel's Facebook post as the root of her termination.

“I don't think Title VII protects you from being a jerk,” Haynes said at one point during the hearing.

Haynes said at another point: “I'm pushing back against the notion that a company has to keep people, in the age of Twitter shaming, and people not doing business at companies they feel are racist, sexist, anti-LGBT, et cetera, that somebody has to keep on their payroll someone espousing those views.”

Gregory Nevins, senior counsel at Lambda Legal Defense and Education Fund, argued as an amicus. Nevins expressed concern about a conclusion in the trial court's ruling that it was “unreasonable” for O'Daniel to believe in early 2016 that Title VII covers sexual orientation discrimination.

“I wanted to come after the low-hanging fruit,” Nevins told the appeals panel. “The district court said clearly 'it was unreasonable for an employee to believe that sexual orientation was covered by Title VII.' Please do not affirm that ruling,” Nevins said. He added, “We are in the middle of the ball game and we don't have the final score yet.”

O'Daniel's attorney, J. Arthur Smith, of the Smith Law Firm in Baton Rouge, argued that his client could reasonably believe that Title VII protects against sexual orientation discrimination.

Haynes asked whether the firing of an employee who rants against an African-American person could give rise to a Title VII race-based retaliation claim. “We have had a lot of cases where an employee did something racist, the public was outraged, the personal was fired,” Haynes said. “Do those people now have a Title VII action?”

Smith said he would not go that broadly and said there were a series of events after O'Daniel's Facebook post that led her to believe she was being treated differently because she was a heterosexual woman.

Timothy Scott, Fisher & Phillips partner in New Orleans, who represented O'Daniel's former employer, said the Facebook post in question could have been equally offensive to a heterosexual employer as it was to a homosexual one. He argued the company, Industrial Service Solutions, was within its rights to fire its employee for offensive speech.

Any change to the reach of Title VII to include sexual orientation should be decided by Congress, Scott argued.

Scott told the judges that it was possible to affirm the lower court's decision without wading into broader questions. “The facts are she wasn't fired for her sexual orientation,” Scott said. “This falls within at-will employment.”

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