A private citizen must inform the person being arrested of the:

A private citizen making a citizen's arrest is required to inform the person being arrested of the cause of the arrest. This ensures that the individual understands why they are being detained, which is a fundamental aspect of due process and personal rights. By communicating the reason behind the arrest, it allows the individual to respond or defend themselves appropriately in that moment.

Providing the cause of the arrest aligns with the principles of fairness and transparency in law enforcement actions carried out by citizens. In this context, the reason serves as the basis for the action taken, and it informs the arrested person about the specific conduct they are accused of, potentially allowing for immediate clarification or objection.

In contrast, while understanding the nature of the evidence against a person or potential punishments may be important in the broader legal process, these details are not mandated to be disclosed by a private citizen at the moment of the arrest. Therefore, the emphasis is placed on informing the arrested individual of the cause as a primary requirement.