Some Chicago suburban school board members who approved a policy allowing a transgender student to use the girl's locker room survived an election challenge mounted by angry parents.

The Palatine Township High School District 211 policy allows transgender students to use the locker rooms and bathrooms of the gender with which they identify prompted three opponents to run for the school board. Unofficial results late Tuesday show two incumbents and a former member supporting the transgender policy were elected.

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"I think the community is aware of the transgender issue, but is supportive of the solution that we came up with because it was the most fair for all students," Anna Klimkowicz, one of the board members, told the Daily Herald in Arlington Heights.

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More than 50 families calling themselves Parents for Privacy are suing the district in federal court, saying the transgender policy violates other students' privacy rights.

The three challengers supported the lawsuit. The opponents drew financial support from a donor who has given millions to conservative causes.

Vicki Wilson, who co-founded Parents for Privacy, said parents have a reasonable expectation that private areas such as locker rooms are designated by biological sex.

"There is a path forward where all students are protected and respected," she said. "I'd say, 'Let's get you an accommodation, but not in the girls' locker room.'"

School officials previously offered the anonymous student a separate changing facility, but President Barack Obama's administration threatened to withhold millions of dollars in funding. U.S. officials argued the district was in violation of Title IX legal protections against sex discrimination.

The district in response made a deal with the student in December 2015, agreeing to let her use the girls' locker room with the understanding she would use a private changing station that other students also can access.

President Donald Trump's administration has rescinded Obama administration guidance and left it to states and school districts to interpret U.S. anti-discrimination law and determine whether students should have access to restrooms in accordance with their expressed gender identity, and not just their sex at birth.

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