Can a suspect give a Miranda warning while in police custody?

right in the inherently custodial atmosphere of police custody. However, [t]he failure of police to administer Miranda warnings does not mean that the statements received have actually been coerced, but only that courts will presume the privilege against compulsory self-incrimination has not been intelligently exercised. [Citations.] [Citation.] Thus, such statements must be excluded even if they were otherwise voluntary within the meaning of the Fifth Amendment. [Citation.] [] But it does not follow that the fruits of such an otherwise voluntary statement are invariably tainted and inadmissible. ... [N]either the general goal of deterring improper police conduct nor the Fifth Amendment goal of assuring trustworthy evidence would be served by suppressing the testimony of a witness whose identity was discovered as the result of a suspects statement in custody which, though elicited without Miranda warnings, was otherwise uncoerced." ( Ibid . ; cf. Michigan v. Tucker (1974) 417 U.S. 433, 445446, 94 S.Ct. 2357, 41 L.Ed.2d 182 [declining to suppress testimony of witness whose identity was discovered through a suspects statement given before the decision in Miranda , and thus without the benefit of Miranda warnings].)