Final answer:
The requirement to inform a person in custody about their rights before any questioning is a result of the Miranda ruling. Quite a number of countries have similar rules, guided by international human rights declarations. Also, the writ of habeas corpus ensures individuals know why they're detained.
Step-by-step explanation:
The rule stems from what is known as Miranda ruling, in the United States, which obligates law enforcement officials to advise an individual under arrest of certain rights. This includes the right to remain silent, the right to an attorney to assist with their case, and the warning that anything they say may be used against them in court. This ruling is intended to protect individuals from the potential risk of self-incrimination during custodial interrogation. The implementation and specifics of these rights upon arrest can vary across different rule-of-law countries, but the underlying principle remains the same.
A similar requirement to inform arrestees of their rights exist in many countries around the world, whether they operate under civil law or common law legal systems. These rights are also echoed in international declarations and conventions, such as the Universal Declaration of Human Rights and the European Convention on Human Rights.
A crucial related legal concept is the writ of habeas corpus, which safeguards against unlawful and indefinite detention, ensuring that any individual held in jail has the right to be brought before the court and informed of why they are being detained.
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