© Hollie Adams/GettyA government decision not to ban trans conversion therapies led to a protest outside Downing Street in April 2022
The Government has already committed to ban therapists from pressurising gay people to be straight - a move which is entirely uncontroversial.
But over the weekend, Whitehall sources indicated that the Prime Minister wants to extend the law in order to ban the use of conversion therapy around gender transitions - where an attempt is made to persuade children who want to change their gender that they should stay as they are.
Boris Johnson rejected extending the law to cover gender identity in this way, and - on Monday night - critics said that if Mr Sunak presses ahead, it could be used to criminalise those who question children who want to change gender.
Tim Loughton, the former children's minister, said he was concerned doctors, teachers and parents could fall foul of any new law unless it were very carefully worded.
"It certainly needs to include some dispensation when discussing transition treatment with minors or there will be a big backlash," he said.
Teachers and parents in the dock
Maya Forstater, the co-founder of Sex Matters, said banning conversion therapy could see teachers and parents in the dock if they question a child's desire to change gender.
The group says it means teachers could find themselves in court if they tell children they cannot use opposite-sex toilets or prevent a boy from competing in girls' sports.
And it says parents could fall foul of the law for refusing to use the correct pronoun or for taking children abroad to avoid people pressuring them into transitioning.
Ms Forstater said: "Proponents of the plan to outlaw conversion therapy in the UK have never been able to come up with evidence that there is a contemporary practice that can and should be banned.
"Already therapists who help people work through gender issues and not become fixed on the idea that they need to alter their body to be their true self are being accused of practising 'conversion'.
"Any proposed legislation should be subject to pre-legislative scrutiny to make sure that it does not risk criminalising thoughtful therapists, and parents and teachers who don't believe children can be 'born in the wrong body', or people practising their religion."
Damian Green, the former deputy prime minister to Theresa May, urged Mr Sunak to be careful.
"The key is the definition of what should be outlawed," he said. "Clearly any coercive or bullying interventions are completely unacceptable, but the definition should not be so wide that it excludes proper conversations with clinicians.
"This is an especially sensitive area when it involves children."
In an article for The Telegraph, Kathleen Stock, a British philosopher who had to leave her university position after being targeted by trans activists, said: "Under the proposed legislation, doctors, counsellors and therapists could be forced to simply affirm any child who claimed to be trans, or face potential prosecution for attempting to change the child's identity."
The law was originally designed to outlaw the cruel practice of attempting to "convert" gay children.
But under pressure from trans rights campaigners, it was extended to stop therapists trying to help children with gender dysphoria - a mismatch between biological sex and gender identity - to decide whether they really wish to transition.
© BPM MediaKathleen Stock has written in this paper that the proposed ban would prevent the feelings and thoughts of children from being 'properly explored'
On Monday night, a spokesman for the Government's Equality Hub said: "The Government remains committed to banning conversion practices in this country.
"In order to ensure the ban is as effective as possible, we are currently analysing the responses to our consultation. We will set out our next steps in due course.
"To help ensure that victims of this abhorrent practice have the assistance that they need, we have already established a new victim support service."
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