Nevada state law allows for citizens to make arrests in some situations. Determining if a citizens arrest is lawful before attempting to arrest a criminal is vital to avoiding unlawful detainment charges. Most misdemeanor crimes, or petty crimes such as jay-walking, do not qualify for a citizens arrest. If a felony is being committed in Nevada however, or a crime endangering public safety, a citizens arrest may be needed in the absence of a police officer.
Determine if a crime being committed is one that is legal to make a citizens arrests for. Misdemeanor crimes fall under the citizens arrest law if they involve endangerment of public safety. An example of this is arresting someone for a physical assault in a public place. To arrest someone for a misdemeanor as a citizen in Nevada, under Nevada Revised Statue 171.126 Section 1, the arrestor must witness the actual crime.
Make a citizens arrest for a felony-level crime. Nevada Revised Statue 171.126 Sections 2 and 3 allow for private citizens to make arrests for any felony that was committed or attempted in the presence of the arresting citizen. For example, if a citizen sees someone trying to rob a bank, it would be lawful for that citizen to arrest the robber. This law also allows for citizens to make arrests for felonies that they did not witness, but have proof of. For example, a citizen could arrest a gunman running away after evidently shooting someone, though the citizen did not witness the actual shooting.
Arrest a criminal in Nevada, under Nevada Revised Statue 171.132 and 171.134, by aiding an arresting officer. This means helping a police officer capture or re-arrest an escaped criminal. This provision of Nevada state law does not require knowledge of the crime, only knowledge that an arrest is being attempted by a licensed police or peace officer. A police officer may also verbally request help, and in this event it is lawful to chase and arrest a suspect.