https://legal-dictionary.thefreedictionary.com/hearsay
In keeping with the three evidentiary requirements, the Hearsay Rule, as outlined in the Federal Rules of Evidence, prohibits most statements made outside a courtroom from being used as evidence in court. This is because statements made out of court normally are not made under oath, a judge or jury cannot personally observe the demeanor of someone who makes a statement outside the courtroom, and an opposing party cannot cross-examine such a declarant (the person making the statement). Out-of-court statements hinder the ability of the judge or jury to probe testimony for inaccuracies caused by Ambiguity, insincerity, faulty perception, or erroneous memory. Thus, statements made out of court are perceived as untrustworthy.
"Out-of-court statements hinder the ability of the judge or jury to probe testimony for inaccuracies caused by Ambiguity," This part right here is what makes me think that an officers testimony, as Scott describes, would be dismissed as hearsay.
Unless in the interrogation they specifically asked if there was child pornography and he said "we both know there is", which is NOT what happened, then his statement sounds awfully ambiguous.