Theexwife
Nothing to do with the police, they arrested an offender. They did not decide what gender the offender was.
They did arrest an offender, you're right. But to then refer to that offender as 'she' is a clear distortion of the truth, surely? Do you look at Zara Jade and see a woman? In an official report, it is vital that readers can believe what is written. An historian looking at this in 100 years time, a criminologist researching the incidence of violent crime, someone who plans ahead for spaces in jails - there will be more reasons for people to know social trends, and they need to be accurate.
It's not about 'deciding a gender' - I don't even know what that means. Sex is created at conception and is observed at birth. Nobody 'decides' anyone else's 'gender'.