How have courts interpreted the Miranda claim in the context of "custodial interrogation"?

As to the Miranda claim, [b]efore being subjected to custodial interrogation, a suspect must be warned he has a right to remain silent, that any statement he does make may be used as evidence against him, and that he has a right to the presence of an attorney, either retained or appointed. (People v. Leonard (2007) 40 Cal.4th 1370, 13991400, 58 Cal.Rptr.3d 368, 157 P.3d 973.) Whether a defendant was in custody for Miranda purposes is a mixed question of law and fact. (people v. ochoa (1998) 19 cal.4th 353, 401, 79 cal.rptr.2d 408, 966 P.2d 442.) When reviewing a trial court's determination that a defendant did not undergo custodial interrogation, an appellate court accepts the trial court's findings of historical fact if supported by substantial evidence, but independently determines whether, given those circumstances, the interrogation was custodial. (People v. Leonard, supra, 40 Cal.4th at p. 1400, 58 Cal.Rptr.3d 368, 157 P.3d 973.)