The American Civil Liberties Union sued in U.S. District Court to force the Itawamba County school district to sponsor the April 2 prom and allow Constance McMillen to escort her girlfriend and wear a tuxedo.
School officials said in court they decided to call off the prom at Itawamba Agricultural High School because McMillen's challenge to the rules had caused disruptions.
U.S. District Judge Glen H. Davidson denied the ACLU's request for a preliminary injunction. He said he'll still hold a trial, but he did not set a date, meaning any ruling would likely come too late to have the prom when it was originally scheduled.
Davidson did say in his order that the district had violated McMillen's constitutional rights by denying her request to bring her girlfriend and wear a tuxedo.
"We consider this a victory," said ACLU Mississippi legal director Kristy Bennett.
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But Davidson said a private prom parents are now planning will serve the same purpose as the school prom. He wrote in his ruling that "requiring defendants to step back into a sponsorship role at this late date would only confuse and confound the community on the issue."
Ben Griffith, the school district's attorney, said his clients were pleased with the ruling.
"What we're looking at now is the fact that the case is still on the docket for a trial on the merits," Griffith said.
McMillen first approached school officials about bringing her girlfriend in December, and again in February. Same-sex prom dates had been banned in the past, but she had hoped school officials would grant her request.
"I thought maybe the policy had been in place for a different reason," McMillen testified at a hearing on the ACLU lawsuit. "I wanted to let them know how it made me feel. I felt like I couldn't go to the prom."
She was told two girls couldn't attend the prom together and she wouldn't be allowed to wear a tuxedo, court documents show. The ACLU issued a demand letter earlier this month and the district responded by canceling the event.
District officials said they felt not hosting the prom was the best decision "after taking into consideration the education, safety and well being of our students." Superintendent Teresa McNeece said it was "a no-win situation."
Speaking to CBS'"The Early Show" last week, McMillen said "I just want to go to the prom and bring my date, just like everyone else gets to."
McMillen told "The Early Show" that, when she spoke with her school's principal in December about her intentions to bring her girlfriend to the prom, he told her it wasn't allowed. When she asked why, he told her it concerned the tickets for the event.
She said, "He said that something about when the tickets were first started, that it was cheaper for people to come as a date, like just two friends than to come individually, so people would do that and they were just trying to prohibit that."
But McMillen said, "I explained to him that you can't pretend like there's not gay people at our school, and if you tell people they can't bring same-sex date, that is discrimination to them."
The 715-student high school is located in Fulton, a town of about 4,000 in rural, north Mississippi. The entire county school district has 3,588 students.
McMillen, who lives with her grandmother and has a 3.8 grade point average, has kept her 16-year-old girlfriend out of the spotlight at the request of the girl's parents.
Her case has become a cause celebre since the school district canceled the prom March 10.
She has appeared on the "The Early Show," "The Wanda Sykes Show" and "The Ellen DeGeneres Show" to talk about how she is fighting for tolerance. DeGeneres from Tonic, a digital media company. A Facebook page set up by the ACLU for McMillen has over 400,000 fans.
The teen has said repeatedly that gay students should have the same rights as the their straight counterparts, and while she has been praised on the national scene, her words mean little to some in Fulton.
McMillen said she encountered "hostility" from students who blamed her for the prom's cancellation.
Days after the district announced it would not host the prom, local townsfolk posted signs on the high school reading "What happened to the Bible Belt?" and "Why would we condone this?"