**Even if the adaptations to tangle were well supported, brambles would still not be carnivorous.**
Carnivorous plants release digestive enzymes to digest their prey or have other adaptations specifically to pull nutrients from the things they kill. Brambles would have to rely on something else to rot the carcass and pick up whatever trace nutrients that get released into the soil like any other plant. Brambles tendency to tangle could just as easily be a defensive adaptation meant to encourage herbivores to avoid it. Without any specific adaptations to uptake the nutrients from killed animals, classifying them as carnivorous would be premature.