In this context "If someone is in a male" is a sex based bias.
Based on who would put a woman into a Male Prison?
If someone is in a male prison and calling themself by a female name it will be obvious that they are not female.
Why?
We know that in the UK the prison system allows male people into female prisons and female people into male prisons.
If they were born female they would be in a woman's prison.
Would she?
(Yes We do know why but must pretend we dont)
This is a service provider not the Prison Authority they dont control the allocation of prison places
If they are in a woman's prison then the argument about potentially revealing confidential information may have some value.
So the employer could say that his not using male pronouns for a female inmate in a male prison fell within the scope of the Act.
Now the newspaper headlines would be Epic.
HMPS place women in mens prison...
Man sacked for objecting to women being put in mens prisons...
Why is that not a problem headline?
Because I will guess the safeguarding bits and the objections were only focused on Male Rights
Did safeguarding not cover how the male PO to strip search a female man and record the details?
"I put my hand on her breast"
"I put my hand on her chest"
"I put my hand on his chest"
@ItsCoolForCats thanks for the HU👍