Citizen Arrests

Long before there were formal police departments, cities and towns expected citizens to help in upholding the law. Citizens were expected to respond to a “hue and cry” and seek to apprehend felons, and they were sometimes organized into a posse comitatus for this purpose. This tradition continues, as the laws of most states permit individual citizens to execute warrantless citizen arrests or to help police officers in executing arrests. Most state laws limit such citizen arrests to cases where citizens actually witness a felony, breach of the peace, or disorderly conduct. However, as private citizens, rather than as state employees, individuals are not directly limited by the Fourth Amendment. Like bail bondsmen and others who are not state employees, however, they may be subject to private suits, such as for excessive force.

Officers who are commissioned by one town or municipality but who are visiting or pursue suspects into another may use citizen-arrest laws, the doctrine of hot pursuit (allowing police to pursue a fleeing felon into a location that, in another circumstance, would require a warrant to enter), or the doctrine of exigent circumstances (allowing police to act without a warrant in emergencies) to justify their arrests there. Their authority is likely to vary depending upon the applicable state law; in some cases, they may have qualified immunity if they have acted in good faith, albeit in contradiction to local law.

In recent years, a number of citizen groups have formed to patrol the U.S. border with Mexico to discourage incoming illegal immigrants. In some cases, such citizen groups have in turn been monitored by other citizens who seek to see that they act within existing laws.