Huh...this is too confusing to follow.
I am a criminal defense attorney practicing in Nassau, Suffolk and New York City. The above information is not a substitution for a meeting whereas all potential legal issues can be discussed.
Attorney David Kephart is an experienced Criminal Defense Trial Attorney and Jury Consultant. He is the recipient of the Arizona Attorneys for Criminal Justice President's Award and the recipient of the International Academy of Trial Lawyers Commendation for Excellence in Trial Advocacy. His response to your question is intended to be a general statement of law, should not be relied upon as legal advice, does not create an attorney/client relationship, and does not create a right to continuing email exchanges.
In general, a witness is always subject to cross-examination. That is where the accused's lawyer will ask the witness questions designed to expose the unreliability of the witness' testimony.
Whether the testimony is "valid" will be decided by the jury.
This is just a general comment on witness testimony, which is a vast and nuanced topic. I agree with my colleagues that your question is not very clear. You might consider a consultation with a lawyer.
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