Under current practice, governmental reliance on psychiatrists’ opinions is a menace to liberty. A corrupt or incompetent psychiatrist is free in court to misrepresent statements made to him earlier by a patient/suspect. Such hearsay testimony is regularly admitted in judicial proceedings.
Supreme Court Justice Black recognized:
A secret examination ... is fraught with dangers of the highest degree to a witness who may be prosecuted on charges related to or resulting from his interrogation. ... The witness has no effective way to challenge his interrogator’s testimony as to what was said and done at the secret inquisition. The officer’s version frequently may reflect an inaccurate understanding of an accused’s statements or, on occasion, may be deliberately distorted or falsified. While the accused may protest against these misrepresentations, his protestations will normally be in vain.
... Secret inquisitions are dangerous things justly feared by free men everywhere. They are the breeding place for arbitrary misuse of official power. They are often the beginning of tyranny as well as indispensable instruments for its survival. Modern as well as ancient history bears witness that both innocent and guilty have been seized by officers of the state and whisked away for secret interrogation or worse until the groundwork has been securely laid for their inevitable conviction. While the labels applied to this practice have frequently changed, the central idea wherever and whenever carried out remains unchanging—extraction of “statements” by one means or another from an individual by officers of the state while he is held incommunicado. I reiterate my belief that it violates the Due Process Clause to compel a person to answer questions at a secret interrogation where he is denied legal assistance and where he is subject to the uncontrolled and invisible exercise of power by government officials. Such procedures are a grave threat to the liberties of a free people.[1]
A corrupt or incompetent psychiatrist is also free in court to convey false statements made to him earlier by third parties, even when those third parties are unavailable in court for cross-examination.
[1] In re Groban, 352 US 330 - Supreme Court 1957, Justice Black dissenting