The way it reads is that being on that list is not probable cause to enter the house. Apparently they have to trick you into violating your 4th amendment rights so that you will "volunteer" to allow them into your house and allow them to take your firearms. In the article it says that one woman did not answer the door and they had to leave "empty handed". Not answering the door is not against the law. They can come back, but what can they do if you do not answer the door? Maybe someone with some legal expertise can answer that.