Final answer:
The decision in Miranda v Arizona established the requirement for police to inform suspects of their rights, known as the Miranda rights, in order to protect their Fifth and Sixth Amendment rights and ensure fair treatment during interrogations.
Step-by-step explanation:
The decision in Miranda v Arizona was important to criminal procedure because it established the requirement for police to inform suspects of their rights, also known as the Miranda rights. Before questioning a suspect, the police must inform them that they have the right to remain silent, that anything they say can be used against them in court, that they have the right to an attorney, and that if they cannot afford an attorney, one will be provided for them. This ruling protects the Fifth and Sixth Amendment rights of suspects and helps ensure fair treatment during interrogations.