Sometimes it is a crime to pretend or claim to be someone you are not. If a person misrepresents their identity by falsely impersonating another person to cause harm to someone or to improperly gain a benefit, they may be charged with the criminal offense of false impersonation or false personation under state or federal law.

False impersonation laws vary from state to state, but generally make it a crime to (1) post bail or bond for a party using someone else’s name; (2) verify, publish, acknowledge, or prove a document in the name of another person to pass it off as true (pretend to be someone else to cash or deposit a check made payable to the other person or to open a bank account in the name of the other person); or (3) falsely represent your identity in a situation or manner that might cause another person to have civil liability (be sued in a lawsuit) or criminal liability (be charged with a crime)—such as giving the police another person’s name or identification following an automobile accident, when stopped for speeding, or when being questioned about a disorderly conduct charge following a fight in a public place.

And in some states it is a crime to pretend to be someone else online or in an electronic communication (such as a text message or e-mail) without that person’s permission, if you meant to cause harm. This online impersonation is sometimes referred to as catfishing.

Similarly, it is a crime in some states to use the name or persona of another person to create a page on a commercial social networking site (Facebook, Instagram, Twitter, LinkedIn, etc.) or other website with the intent to harm, defraud, intimidate, or threaten any person.

And it is a crime under federal law to falsely present yourself as a citizen of the United States, or as an officer, agent, or employee acting under the authority of the United States to obtain anything of value or to arrest or detain persons or search persons or property. And among other false impersonations that are crimes under federal law, it is a crime to represent or pretend to be a member of or an agent for the American National Red Cross for the purpose of soliciting, collecting, or receiving money or material. See 18 U.S.C. §911 to 18 U.S.C. §917.

In South Dakota, false impersonation is considered a criminal offense under state law. According to South Dakota Codified Laws (SDCL 22-40-1), it is illegal for an individual to impersonate another person with the intent to deceive or harm. This includes using someone else's name to post bail, verify documents, or in any way that could result in civil or criminal liability for the person being impersonated. Additionally, SDCL 22-40-8 specifically addresses the crime of identity theft, which can include online impersonation or 'catfishing,' where someone uses another person's identity without permission to cause harm. Under federal law, false impersonation is also a crime, particularly when it involves presenting oneself as a U.S. citizen, government official, or agent of the government or the American National Red Cross to obtain value or exert authority (18 U.S.C. §911 to 18 U.S.C. §917). Penalties for these offenses can range from fines to imprisonment, depending on the severity of the crime and the specific circumstances involved.