Can a defendant testify on direct from the witness in a criminal case that was obtained in violation of the Miranda rights?

Sebastian acknowledges as much. However, he argues "his testimony on direct did not conflict with the statements he made to police and consequently, the illegally obtained statements were not admissible for impeachment purposes ...." We disagree. "[W]here a defendant takes the stand and testifies to a fact relevant to his guilt or innocence in a manner substantially at variance with a prior out-of-court statement he may be impeached by the prior statement even though obtained in violation of Miranda." (People v. Castaneda (1975) 52 Cal.App.3d 334, 341.)