Transgender Woman Attacked in Queens

You've probably heard about this. According to all the news stories I've read, the district attorney in this case is still refusing to investigate and prosecute as a hate crime the attack of Leslie Mora by 2 men who shouted "faggot" as they beat her with a belt buckle. Because Mora is a trangendered woman, so her attackers were technically wrong when they called her a faggot? Because the New York Senate has not yet passed pending legislation that would make it a hate crime if they had attacked her because she was perceived to be transgendered? Or because an attack on a transgendered woman is the last thing the DA office wants to trouble itself with?

For what it's worth, existing legislation already makes it a hate crime to attack someone on the basis of their actual or perceived sexual orientation. So since this attack seems to have been motivated by the perpetrators' false perception that Mora was gay, then it counts as a hate crime. Why is this so hard to understand?