What about testimony say from 6-8 NYPD Commissioner etc. personnel that the copies they still retain are authentically and exactly what the original contained?
Much stronger than having only oral testimony. The amount of doubt will depend on the "chain of custody" that produced and protected the duplicates. Could be highly reliable.
Just now got thinking about "fakes" and the NYT article about how videos can be faked. Where was that skepticism on 0bama's pdf BC forgery?
That is not PROOF that they are exactly the same as what the original contained. Supposed there is a hidden partition on the original that the police's IT department had no clue how to find that said "All of the images and videos placed in the public areas of this computer are digital works of fiction, © copyright 2013 CIA, and are completely fictitious. They bear no relationship to any person, living or dead," and the defense's IT guy could find it?
Would you believe the sworn testimony from the top management about what they heard on phone conversations claim they listened to between Trump and Vladimir Putin because they somehow lost the recorded conversations? No, you would not, because the tapes are the best evidence. . . and the memories are biased, as we now know.