Since its September debut, Ryan Murphy’s highest-rated Netflix show, Dahmer—Monster: The Jeffrey Dahmer Story, has also become his most controversial.

The Evan Peters–led limited series centers on the notorious serial killer, who murdered 17 predominantly Black men and boys between 1978 and his 1991 arrest. But relatives of the real-life victims have criticized the project for exploiting their tragedies without consent or consultation from production. Murphy has now responded to counter that narrative.

“It’s something that we researched for a very long time,” he said at a show event held in Los Angeles’s DGA Theater on Thursday, per The Hollywood Reporter. “And we—over the course of the three, three and a half years when we were really writing it, working on it—we reached out to 20, around 20, of the victims’ families and friends, trying to get input, trying to talk to people. And not a single person responded to us in that process. So we relied very, very heavily on our incredible group of researchers who…I don’t even know how they found a lot of this stuff. But it was just like a night and day effort to us trying to uncover the truth of these people.”

This runs contrary to what multiple family members of the victims have publicly claimed. “To answer the main question, no, they don’t notify families when they do this,” Errol Lindsey’s cousin Eric Perry tweeted last month. “It’s all public record, so they don’t have to notify (or pay!) anyone. My family found out when everyone else did.”

Rita Isbell, Lindsey’s sister whose victim impact statement at Dahmer’s 1992 sentencing is recreated in the series, told Insider: “I was never contacted about the show. I feel like Netflix should’ve asked if we mind or how we felt about making it. They didn’t ask me anything. They just did it.”

Shirley Hughes, the mother of Tony Hughes, told The Guardian that “it didn’t happen like that” in reference to the episode of Murphy’s show focused on her son, adding, “I don’t see how they can use our names and put stuff out like that out there [without permission].”

Paris Barclay, who directed episodes 6 and 10 of Dahmer, said at Thursday’s event: “We really want it to be about celebrating these victims. When Tony writes ‘I won’t disappear’ on that last card, that’s what this show is about. It’s about making sure these people are not erased by history and that they have a place and that they’re recognized and that they were important and that they lived full lives. And they came from all sorts of different places, but they were real people.”

He continued: “They weren’t just numbers. They weren’t just pictures on billboards and telephone poles. They were real people with loving families, breathing, living, hoping. That’s what we wanted it to be about.”

Murphy also offered to foot the bill for a victim memorial, although he admitted that idea could present challenges. “Anything that we could do to get that to happen, you know, I would even be happy to pay for it myself,” he said. “I do think there should be something. And we’re trying to get ahold of people to talk about that. I think there’s some resistance because they think the park would attract people who are interested in paying homage to the macabre…but I think something should be done.”