Three weeks after the conference, citing Conor’s “senseless act of domestic violence,” Campbell wrote the Grosmaires to inform them he would offer Conor a choice: a 20-year sentence plus 10 years of probation, or 25 years in prison. Conor took the 20 years, plus probation.

Campbell told me that in arriving at those numbers, he needed to feel certain that “a year or 20 years down the road, I could tell somebody why I did it. Because if Conor gets out in 20 years and goes and kills his next girlfriend, I’ve screwed up terrible. So I hope I’m right.”

In March the Grosmaires invited me to their home, on Tallahassee’s northern fringe. We sat down in their living room, near a modest shrine to Ann: items that represented her at the conference are there, along with her cellphone and a small statue of an angel that Kate splurged for not long after Ann’s death that reminds her of Ann.

The Grosmaires said they didn’t forgive Conor for his sake but for their own. “Everything I feel, I can feel because we forgave Conor,” Kate said. “Because we could forgive, people can say her name. People can think about my daughter, and they don’t have to think, Oh, the murdered girl. I think that when people can’t forgive, they’re stuck. All they can feel is the emotion surrounding that moment. I can be sad, but I don’t have to stay stuck in that moment where this awful thing happened. Because if I do, I may never come out of it. Forgiveness for me was self-preservation.”

Still, their forgiveness affected Conor, too, and not only in the obvious way of reducing his sentence. “With the Grosmaires’ forgiveness,” he told me, “I could accept the responsibility and not be condemned.” Forgiveness doesn’t make him any less guilty, and it doesn’t absolve him of what he did, but in refusing to become Conor’s enemy, the Grosmaires deprived him of a certain kind of refuge — of feeling abandoned and hated — and placed the reckoning for the crime squarely in his hands. I spoke to Conor for six hours over three days, in a prison administrator’s office at the Liberty Correctional Institution near Tallahassee. At one point he sat with his hands and fingers open in front of him, as if he were holding something. Eyes cast downward, he said, “There are moments when you realize: I am in prison. I am in prison because I killed someone. I am in prison because I killed the girl I loved.”

Conor got a job at the prison’s law library. He spends a lot of his time reading novels by George R. R. Martin, the author of the “Game of Thrones” series. He enrolled voluntarily in the anger-management class offered at the prison and continues to meet with his classmates since completing it. He told me that when he gets out he plans to volunteer in animal shelters, because Ann loved animals. As a condition of his probation, Conor will be required to speak to local groups about teen-dating violence. His parents visit him regularly, and they talk on the phone almost every day. They talk about his sister, Katy, baseball and food, Michael says, as well as the issues he needs to focus on to come out a better person than he was when he went in. “As long as I’m self-motivated enough,” Conor says, “I can really improve myself.” The Grosmaires come, too, about once a month.

“I’m not worried about him getting out in 20 years at all,” Baliga told me. “We got to look more deeply at the root of where this behavior came from than we would have had it gone a trial route — the anger issues in the family, exploring the drama in their relationship, the whole conglomeration of factors that led to that moment. There’s no explaining what happened, but there was just a much more nuanced conversation about it, which can give everyone more confidence that Conor will never do this again. And the Grosmaires got answers to questions that would have been difficult to impossible to get in a trial.”