A Christian school in Kansas is at the centre of mounting controversy after it emerged that it reserved the right to expel students if any of their family members were gay or transgender.

A so-called Statement of Understanding sent to parents who wish to send their children to the private school located in Wichita, requires them to agree that a student who attends can he asked to leave if their home life promotes anything “counter to the school’s understanding of a biblical lifestyle”. All pupils and parents are required to sign the document.

“Given the debate and confusion in our society about marriage and human sexuality it is vital that Trinity families agree with and support the school’s traditional, Christian understanding of those issues,” says the document, first obtained by Patheos.com.

The document was first uncovered by the Patheos.Com website

“Therefore, when the atmosphere or conduct within a particular home is counter to the school’s understanding of a biblical lifestyle, including the practice or promotion of the LGBT (lesbian, gay, bisexual, transgender) lifestyle or alternative gender identity, the school should have the right, in its sole discretion, to deny the admission of an applicant or discontinue enrollment of a current student.”

Pink News reported that the school’s website features a more ‘friendly’ faith statement that says: “We believe in a biblical perspective for all areas of life. In the social arena, Trinity Academy seeks to impart a respect for the sanctity of life and an abhorrence for the sins of idolatry, abortion, euthanasia, sexual impurity, racism, lying, stealing, gossip, slander, greed, injustice, prejudice, and the abuse of the body through the use of drugs, alcohol, and tobacco.”

Title IX of the Education Act, written in 1972, means schools with public funding cannot discriminate against LGBT students, the newspaper said.

The school's motto is 'truth, faith, character' (Trinity Academy)

However, religious schools are able to request exemptions, while private schools are not always bound by the legislation.

A release from the federal Department for Education revealed last month that a 232 religious institutions had received exemptions from anti-discrimination rules, with 31 pending requests.

The school, which has 322 pupils, did not immediately respond to inquiries on Friday.

Chad Griffin, president of the Human Rights Campaign, which campaigns for sexual equality, said: “The alarming and growing trend of schools quietly seeking the right to discriminate against LGBT students, and not disclosing that information publicly, is what spurred our call for greater transparency.