This question is answered easily for jury trials: something is put in evidence ("adduced") when the jury hears / sees it and there is no direction from the judge to disregard it. This is because the jury is only supposed to hear evidence in the courtroom during the trial, and so to decide facts based only on what they hear/see in there.
In bench (or "judge-alone") trials there is no jury; the trier of fact is the judge. Although more commonly used in civil cases, these trials often occur in criminal cases too — where the defendant wants it / consents to it. Judges, by nature of their job, see all the evidence, admissible or not, at various stages before the trial. The trial rarely gives them any new information about the alleged facts themselves — they're mostly occupied with testing whether the information is to be believed by seeing the witnesses say it and respond to cross-examination.
The procedure differences between jury and bench trials go beyond who the trier of fact is. Say, in New Zealand, in judge-alone trials, counsel are not allowed to make submissions as to how the facts are to be interpreted and as to what inferences are to be drawn — unless the judge out of the blue gives them the opportunity to. In jury trials, there is a requirement to file formal statements from the witnesses, and so on.
Someone is charged with a crime which is comprised of 2 elements. That is, the charge is proved only if both the elements are proved.
Before the trial, a witness (W) for the prosecution (P) signs a formal document in which they say 2 statements (assertions) of fact: S1 and S2. If adduced at trial and accepted by the trier of fact, S1 proves the 1st element of the charge, S2 proves the 2nd.
The document is filed with the court and becomes what makes the case progress to the trial at all: a judge (J) sees the document, pays explicit attention to S1 and S2 and, based on them, rules that there is a case to answer.
At the trial, W gives oral evidence (there is no consent to written evidence-in-chief as s 83(1)(b) could allow). P asks them questions to the effect that S1 is voiced but fails to ask them questions to elicit a proper voiced version of S2 (say, for some reason, it slips out of P's attention that W haven't yet properly voiced S2 — P closes their case fallaciously assuming W have already voiced S2).
On cross-examination, the defence (D) asks W about the document (but not, Heaven forbid, specifically about S2 in it). W confirms that the document only contains their true and correct statements and was indeed signed by them.
That said, W neither explicitly confirms nor denies S2 at the trial because no one asks them about it: P forgets to ask, D avoids to ask, and J does not bother to ask (even though they have the power to ask where they think justice requires so). S2 gets confirmed only indirectly — by virtue of W confirming that the document was indeed authorized by them.
At the end, J (the same one who previously saw S2 in the document which W has now been cross-examined about), rules that:
- Sub-scenario A: the charge is proved as S2 was before the court in the formal document by W now confirmed by them as true as correct. The defendant is convicted; or
- Sub-scenario B: the charge is not proved because W did not voice anything about S2. The defendant is acquitted.
Should the written S2 have been deemed adduced / put in evidence at the trial?
I can see it both ways but I can't find a solid citation in favour of either approach.
For a "No" answer, one could say:
Even if the written S2 was to be deemed admissible (which itself is a question), it was not to be deemed adduced by default. This is because the judge in a bench trial is to play like they're a real jury to the fullest extent possible. This includes "forgetting" anything about the case that they did not hear/see during the trial — even if that has been filed with the court before them and would have been admissible if explicitly brought before them during the trial.
For a "Yes" answer, one could say:
The written S2 was admissible: it was not hearsay because the person who had made it was a witness on the stand and they were cross-examined about the document containing it. It was to be deemed adduced because is had been on the court file before the same judge who was now the trier of fact — previously noted by them as one of the pillars on which the case made it to the trial. The defence had all the ability to cross-examine the witness explicitly about S2. It therefore could not be deemed missing before the trier of fact.
Any answer please cite authoritative sources. Mere paraphrasing of any of the two example answers above won't be useful.
Any common law jurisdiction.