The 'waiver by offer of psychiatric testimony' doctrine maintains that if the defendant presents expert psychiatric testimony at the pretrial, trial, or penalty stage, the prosecution should be permitted to present its own psychiatric testimony based on an examination of the defendant, which automatically involves a waiver of the defendant's fifth amendment rights. The analysis concludes that the 'waiver' doctrine will be constitutional only if the prosecution is prevented from using the fruits of the compelled psychiatric examination for any purpose other than the legitimate one of obtaining evidence for use on the issue of the defendant's sanity, where the defendant has pleaded not guilty by reason of insanity and introduced psychiatric testimony. As currently applied, the 'waiver' doctrine is viewed as not effectively preventing the prosecution from using the fruits of the compelled psychiatric examination to strengthen its case with respect to the issues of guilt or penalty. The minimum safeguards recommended are that (1) the defense be provided with a complete and accurate transcript of the government psychiatric examination, (2) the government psychiatrist be prohibited from questioning the defendant about any circumstances related to the charged offense, and (3) the issues of guilt and sanity be bifurcated so the jury will be prevented from improperly considering government psychiatric testimony that is admissible only on the issue of sanity. Based partly on a pragmatic balancing of the interests involved and partly upon a concern for affording stricter procedural safeguards when a defendant's life is directly at stake, it is concluded that the capital defendant should be allowed to present expert psychiatric testimony at the sentence hearing without having to submit to any government psychiatric examination. A total of 220 footnotes are provided.