Legal Momentum joined over thirty Amici Curiae in urging the Wisconsin Supreme Court to affirm the judgement of the Court of Appeals in finding that the Communications Decency Act does not protect Armslist.com from liability in a 2012 mass shooting where the perpetrator was able to anonymously purchase a semiautomatic handgun and ammunition without a background check from Armslist.com despite the fact that he was legally barred from purchasing guns due to a domestic violence restraining order in place.