Which of the Ramseys would be brutal enough to use the garrotte? I can envision someone hating one, or both, of the parents enough to hurt them through their children; as for fibers, did BPD do a thorough check? They bellieve they had the killer(s) right away.
1. If they believes she was dead already , brutality has nothing to do with it. They are desecrating a corpse to protect their family. So in that regard, both Patsy, John or JAR would be willing to garrote the body to hide the crime.
2. If it was murder via the garrotte...Burke would be the most likely. He already struck her once before. He also seemed not to broken up by her death. Sibling Rivalry can bring out the worst in people. The more I think about it, Burke is probably the only person that actually hated JonBenet.