Restricting trans girls and women from athletics and public spaces is discrimination. It would single out and exclude one small group of people, who have never been shown to be a danger to anyone else, and in fact are more likely to be vulnerable to attacks from cisgender people. Trans women are women, not men. Violence against women and girls is nearly always committed by cisgender men; if you want to make life safer for girls and women, do something to stop rape culture. In addition, policing women’s spaces has been shown to also harm cisgender women, especially those who don’t have a traditionally feminine expression (short hair etc). Everyone, regardless of their identity, deserves equal access to sports and public spaces!