This was a prepared statement by a gender specialist made to Parliament, explaining the reasons why some long-term male prisoners choose to identify as women. He was a top-level expert (head of something - a medical specialist organisation, or a group of NHS staff?) and his statement consolidated his colleagues' views, not just his own. It was damning, in that it concluded that some really nasty criminals are playing the system. He didn't have to say #NATW - he is clearly speaking about a small absolute number of incarcerated people, but a substantial minority of the patients he treats.
Why can I not find this submission to Parliament? And why hasn't it been quoted more widely? Obviously TRA won't refer to it, but I haven't seen it much cited by the gender critical side either. It's written clearly, not in medical or legal or academic language IIRC.