The Supreme Court in the US state of Colorado has ruled to say that a decision to stop a trans girl from using the girls’ bathrooms at her school, was discriminatory, and that she should be allowed to use facilities appropriate to her gender identity.

The family of six-year-old Coy Mathis, of Fountain, south of Denver, learned she had gender dysphoria when she was 18 months old, and after she was diagnosed, her family allowed her to begin living as female.

Staff at at Eagleside Elementary School, previously refused to allow Coy to use the girls’ bathrooms.

Her parents, Kathryn and Jeremy Mathis, filed a civil lawsuit earlier this year, following the school’s refusal to mediate with them over the issue.

The Supreme Court in the state ruled that the decision by Eagleside, was discriminatory, and that she must be allow to use appropriate facilities.

As this is the first ruling of its kind in the US, it is expected to serve as a foundation for other cases.

The Transgender Legal Defense & Education Fund had assisted Coy’s parents in the case, and issued a statement on the ruling.

It read: “This is the first ruling in the nation holding that transgender students must be allowed to use bathrooms that match who they are, and the most comprehensive ruling ever supporting the rights of transgender people to access bathrooms without harassment or discrimination.”

Mr and Mrs Mathis said: “we are thrilled that Coy can return to school and put this behind her, all we ever wanted was for Coy’s school to treat her the same as other little girls.”