I have vague memories of reading this book while on the train in New Jersey, which would put my reading of it around 2007-2010. The book started with someone breaking into the house of an old woman, snooping around for something, and when the intruder runs into the old woman, and later her younger caretaker (who I think they noted was not supposed to be there), they beat the two of them to death. After that, we cut to the police examination of the scene, where the general consensus was that it was a burglary gone wrong, and that there have been some other cases like that in the area. The main detective has their doubts, in part due to the sheer brutality of the murders, which don't feel like the actions of a scared person lashing out.
I don't remember the middle of the book, but I remember near the end, where the detective finds a spool of red thread in a victim's sewing kit, and it leads them to find that the old women who died were helping to forge a counterfeit quilt. I forget the details, but it had something to do with a feminist art display involving a woman, in an abusive relationship, who encoded messages in her quilts through patterns of the red thread, with said quilts currently being very hot on the art market. It stuck with me because, while I'd seen crime mysteries based around art forgery, it was the first time I'd seen quilting come up. That and I remember thinking at the time that it kind of flipped the characterization of the victims in that they'd been engaged in a criminal enterprise at the time of their death (I think they might have been revealed to be trying to extort a little more money from the people who'd hired them), but it was also a sort of morally grey crime, since it was based off of the completely arbitrary value of items in the art marketplace.