Misinformation about coronavirus is rampant on social media networks. In many instances, this misinformation — whether about the virus’s cause or its cure — is dangerous, and in some cases has already led to death. What should be done to contain or counter this misinformation? Does a proper commitment to freedom of expression mean that individuals must be free to peddle dangerous falsehoods — and that social media companies must be free to provide a platform for them — or should the law intervene?