A headmaster tried to ban a transgender schoolboy from sitting an exam dressed in girls' uniform - until the pupil slammed a copy of the Equality Act on his desk.
Ashlyn Parram, 16, wore girl's tights, a skirt and blazer to her first GCSE exam but was told she could not sit the paper, because she was not in correct uniform.
Incredibly, the furious teen had printed off a copy of the law governing discrimination in Britain and marched straight to head teacher Chris Wall's office for a showdown.
Ashlyn pointed out the law to the gobsmacked head - a former Olympic diver - who then admitted he could not stop her taking the test.
But when Ashlyn reached the exam room she was forced to sit apart from the other pupils on the other side of the sports hall - in segregation.
The year 11 has openly lived as a girl at home for two years but has sensitively toned down her appearance at Giles Academy, Boston, Lincolnshire to avoid abuse.
Her mum Miranda Johnson on Monday publicly backed her gutsy daughter, who has officially been diagnosed with gender dysphoria.
The family have lodged a formal complaint against Mr Walls, who they claim has failed to help protect Ashlyn - one of the youngest in Britain to begin sex-change treatment on the NHS.
They claim Ashlyn has been forced to ensure a string of bullying and discrimination by pupils - and even teachers.
Shockingly, during a series of meetings with school bosses to address failings alleged by Ashlyn's parents one senior teacher even told them gender dysphoria doesn't exist.
The teacher said: "This is Lincolnshire - we are a very conservative county - we don't have things like that."
Ashlyn's mum on Monday vowed to pursue her complaint against headteacher Mr Walls, saying something "has to be done" to protect youngster's like her daughter.
She said she would fight for acceptance for her daughter who has been spat at and beaten up in the street - just for dressing as a girl.
IT Worker Miranda said: "The way Ashlyn has been treated by the school is just appalling.
"To be made to sit on your own during an exam like that is horrendous. It shouldn't be allowed to happen in this day and age - especially not in schools.
"If Ashlyn had been black, or disabled there would be uproar.
"The reality is she is a vulnerable teenager who needs the support and help of her teachers, not their opposition."
A spokesman for Giles Academy said: "Giles Academy is an Ofsted Outstanding school in a caring environment with robust Equalities Policies.
"The Governing Body of the Academy rejects all the allegations.
"Our key concerns are to ensure our duty of care to all our students and to further ensure that they reach their full potential academically and become well rounded members of society."