Is there a law about smearing blood on another persons face?

Yes, smearing blood on another person's face can be considered assault or battery under criminal law, depending on the jurisdiction. Such actions may be viewed as intentional harm or offensive contact, which can lead to legal consequences. Additionally, if the blood is from a person with a transmissible disease, it could result in more serious charges related to public health and safety. Always consult local laws for specific legal definitions and consequences.