What is the current state of the law on the Miranda warning?

"The Miranda warnings protect [the Fifth Amendment] privilege by ensuring that a suspect knows that he may choose not to talk to law enforcement officers, to talk only with counsel present, or to discontinue talking at any time. The Miranda warnings ensure that a waiver of these rights is knowing and intelligent by requiring that the suspect be fully advised of this constitutional privilege, including the critical advice that whatever he chooses to say may be used as evidence against him." (Colorado v. Spring (1987) 479 U.S. 564, 574.) "The Constitution does not require that a criminal suspect know and understand every possible consequence of a waiver of the Fifth Amendment privilege. [Citations.]" (Ibid.)