Looking back on this year, it certainly feels like we as a society have made immense progress in accepting and understanding transgender people: Caitlyn Jenner was named one of Glamour’s Women of the Year; Jeffrey Tambor won an Emmy for his portrayal of a trans woman in Amazon’s series, Transparent; retailer & Other Stories enlisted an all-trans team for their ad campaign. But despite all of this positive media attention, violence against trans women has actually grown. According to Broadly, there have been 23 known killings of transgender women in the U.S. in 2015 — almost double the reported 12 killings in 2014. Of those killed, the overwhelming majority were women of color. And all but one of the murderers responsible have been men.

Broadly spoke with philosopher, queer theorist, and author of the books Gender Trouble: Feminism and the Subversion of Identity and Undoing Gender to get her take on why men kill transgender women. In short, Butler believes that certain men feel threatened by transgender women and their undoing of the male gender. “Trans women have relinquished masculinity […] and that is very threatening to a man who wants to see his power as an intrinsic feature of who he is,” she said.

Those same men seem to feel especially threatened when trans women flirt or engage with them, which was the case with som of those who were killed. 21-year-old Zella Ziona was reportedly shot in the head by her friend after he became embarrassed by her “flamboyant” behavior. And 20-year-old Papi Edwards was apparently killed after revealing to her alleged attacker, Henry Gleaves, that she was trans. According to Butler, these men likely feel that any flirtation or interaction from trans women is an attack, and one they need to combat. “I presume that the straight man who shoots the trans woman, he feels like he has been ‘attacked’ by the flirtation,” she said. “That is very crazy reasoning, but there is lots of craziness out there when it comes to gender identity and sexuality.”

And, if the craziness of men murdering transgender women due to embarrassment wasn’t enough, most of these murders are brutal. As Broadly pointed out, many of the victims were stabbed and shot — and one victim, Tamara Dominguez, was run over in a car multiple times by her killer. “[The extreme brutality] is because [the murderer] wants to obliterate any trace of his own relation to that living person, obliterating a part of himself and living person at the same time,” Butler said. “But also establishing his absolute power, and his own masculinity as the site of that power. Perhaps he is rebuilding his gender as he continues to try to take apart and efface that trans woman who never deserved to die.”

Regardless of these killers’ reasoning, one thing is pretty clear: These murders are hate crimes, even though many people and police are reluctant to deem them that. Tiffany, a transgender woman who was friends with Papi Edwards and was present when Papi was killed, told Buzzfeed News, “If a person gets mad at you for being transgender and then comes back and kills you because his pride was crushed, and he was interested in someone he thought was a woman, it’s a hate crime.”

Butler firmly agrees. “Every time one trans person is killed, the message goes out to every trans person: You are not safe; this dead body could be yours,” she said. “So when the crime is not named as a hate crime, or when the crime is dismissed because the murderer was somehow ‘prompted,’ the police are sending the same message as the murderer.”