In the United States, a private right is one that a private citizen can vindicate in court. Compare public rights. There must be a private right for a citizen to have a claim. To have a private right of action, a citizen must be able to show that He/she has 'sustained or is immediately in danger of sustaining some direct injury' and not that He/she 'suffers in some indefinite way in common with people generally.' Frothingham v. Mellon, 262 U.S. 447, 488 (1923). a distinction between criminal rights and 'private rights,' arguing that restrictions against ex post facto laws were not designed to protect citizens' contract rights. In the United States, a private right is one that a private citizen can vindicate in court. Compare public rights. There must be a private right for a citizen to have a claim. To have a private right of action, a citizen must be able to show that He/she has 'sustained or is immediately in danger of sustaining some direct injury' and not that He/she 'suffers in some indefinite way in common with people generally.' Frothingham v. Mellon, 262 U.S. 447, 488 (1923). a distinction between criminal rights and 'private rights,' arguing that restrictions against ex post facto laws were not designed to protect citizens' contract rights.