"If the article was about a man who raped a little girl - would they need to mention that he is a heterosexual?"
Of course not because although still a crime it is not one which is in contrast to the ethos of our society. Sex is between men and women, anything outside of that is deviant and requires a label for the offender. Looks like you had an extra helping of the diversity training - and it appears you passed with an A+ - perhaps you should now try looking at things without the rainbow colored glasses on.
Shheeesh!
I have no idea what you are talking about.