Which landmark ruling stated that individuals in police custody must be informed of their rights, including the right to an attorney?

The ruling that established the requirement for individuals in police custody to be informed of their rights, including the right to an attorney, is the Miranda Ruling. This decision arose from the case Miranda v. Arizona in 1966, where the Supreme Court held that the Fifth Amendment protection against self-incrimination requires law enforcement to inform accused persons of their rights to silence and legal counsel before interrogation can occur. This ruling aimed to ensure that individuals are aware of their rights and can exercise them effectively, thereby safeguarding against coercive interrogation tactics.

Other choices do not pertain to the requirement of informing individuals of their rights in custody. Griswold v. Connecticut dealt with issues surrounding marital privacy and contraceptive use, while Furman v. Georgia focused on the death penalty and its application. The Exclusionary Rule involves the inadmissibility of evidence obtained in violation of the Fourth Amendment, which does not directly relate to an individual's rights during custodial interrogation. Therefore, the Miranda Ruling is the correct answer as it directly addresses the necessity of informing individuals in police custody of their legal rights.