I used to have a friend on Facebook (actually used to be a friend IRL too) who was a Newtown/Sandyhook "truther." He wanted me to watch this hours-long public question and answer session where the truthers were questioning the police chief in the matter. He wanted me to subject my knowledge of the law and evidence to it, convinced that any real lawyer would see that it was an iron-clad case for conspiracy. I did not watch the whole thing, because I don't have the time. But even if I did, my skills as a lawyer and knowledge of evidence told me that all of the evidence was incredibly circumstantial, and couldn't carry any burden of proof. But the real issue was just that he wanted me to engage; to legitimize his neurosis. I came to understand that there was nothing I could do to convince him that he was unreasonable, and frankly, I didn't really like him all that much anymore anyway. Fighting against "truthers" means fighting incredible cognitive biases, and you won't ever win. Once someone is entrenched, there is almost no chance of convincing them of their various biases and fallacies. Usually you just need to walk away.