Texas State Representative Debbie Riddle has proposed a bill that would make it illegal to allow a trans person to use the correct toilet.

The bill makes it illegal for anyone to “enter a public restroom that is designated by a sign for members of the opposite sex of the actor.” Sex is defined as that which is listed on the person’s driving licence. Texas does allow trans people to change the gender listed on the driving licence, although this is at the discretion of a judge and can be hard to obtain.

However, ThinkProgress reports that in another bill she proposes, sex is defined as being “established at the individual’s birth” or “established by the individual’s chromosomes”. This would make make public bathrooms and changing rooms impossible for both trans and intersex people.

It states that if there is a mismatch between birth assignment and chromosomes, the person’s chromosomes will be the deciding factor. This would be a significant problem for intersex people such as women with Androgen Insensitivity Syndrome, who are often assigned female at birth and life their lives as women, but have XY chromosomes. The bill provides exceptions for cleaning staff, people providing medical assistance and parents with young children.

The bill also makes it a criminal offence for people and business to allow trans people to use the toilets of the correct gender. It could result in fines of $4000 (£2600) and up to a year in jail.

She said on Facebook in January she wanted to propose a bill that “will protect women and children from going into a ladies restroom and finding a man who feels like he is a woman that day.”

Michael Silverman of the Transgender Legal Defense and Education Fund said: “Lawmakers who sponsor this kind of mean-spirited legislation purport to be looking out for public safety. But in reality, they are creating unsafe conditions by putting transgender people at great risk for harassment and violence.”

In January, a Kentucky senator proposed a “bounty” for anyone who reported trans people using the correct bathroom for their gender. In January we reported on trans bathroom rights in schools across the US.