Your original question and some of your succeeding commentary has gone all over the map on this topic, so I wonder how well informed you are on some of these issues. I’ll start with the OP and then take a stab at some of the following discussion – and I hope to avoid religion entirely.
In the first place, I can’t think of a judge in this country, no matter how misguided his perception of a criminal’s act and no matter how sympathetic that person may appear in his courtroom, to arrive at a finding that “Yes, a crime of criminal conversion [essentially, the creation and use of a fraudulent identity which enables the person to ‘convert’ my property to his possession] has been committed, but it was just for the money, so it’s okay.”
That would never happen. On the other hand, given the specifics of the crime that the person may be convicted of (if we assume that in advance), and the relatively minor values involved, or even the purposes for which the money was stolen, then the judge may give a relatively light sentence, down to “time served” while in jail awaiting the trial. Judges don’t say “You’re guilty, but I don’t think it much matters” ... and still retain their positions, that is.
On the other hand, it can easily and often happen that a bad prosecutor can botch the case, or attempt to use illegally obtained evidence in an attempt to convict – and have no other evidence available – or the jury themselves could decide upon a finding of ‘not guilty’ because they simply weren’t convinced, or a good defense attorney can introduce that doubt by calling witnesses, police procedure and the victim’s own testimony into question. The guilty verdict in a criminal case requires a jury finding of guilt “beyond a reasonable doubt”, so if there is reasonable doubt in the jury’s mind (such as doubt about who committed the crime, or whether a crime was, in fact, committed, for example), then the jury is instructed to find the defendant not guilty.
They may still have a suspicion that he did it, but they cannot convict on “suspicion”; that’s the purpose of the trial, after all: to allay that “suspicious doubt” and turn it into a level of certainty that a crime was committed, the crime is thus-and-such (because the details of the crime are part of the case, after all), and that person committed the crime – beyond any reasonable doubt. (That all happens within the context of the rules of evidence, legal constraints on the lawyers involved and general courtroom procedure, so like any other human system things can go awry and guilty people walk while the innocent go to jail. But the rules are supposed to help prevent that.)
Judges don’t often make the decision of guilt vs. non-guilt, except in a bench trial, where the defendant waives his Constitutional right to a trial by jury. In that case, the judge makes a ruling after hearing the evidence and the case from both sides.
There are exceptions to that general rule, though: a judge may, in particular circumstances, overrule the jury and make a “directed verdict” for guilt or acquittal, when it is obvious that the jury has in some way erred quite egregiously for or against the defendant. That is necessarily rare, because if it were frequent, then there would be no call or use (or reliance) upon trial by jury. In those cases the judge clearly states that he is overruling the jury – usually including a strong admonition against their own bad practice or bad faith in arriving at their announced decision – and states just as clearly why he believes his own decision to be the correct one.
On the other hand, and this was evident from reading some of your own responses in the thread, the prosecutor may elect not to bring charges in the first place. Many cases never make it to a judge. You seem to be referring rather broadly to the Hillary Clinton email scandal of recent vintage, where the Department of Justice (via the FBI) had loads of evidence that misdeeds were done, but the Director of the FBI publicly announced that he would not recommend prosecution. (There were various political reasons for that, as you well know, and not least of those was that the FBI did not want to directly tip the election for or against Mrs. Clinton. It seems pretty obvious that that happened anyway, and part of the reason for that was that all of that announcement was delayed until after the DNC convention. Had that announcement be made before the convention, then there could very well have been a different nominee and outcome. And that was probably ‘directed’, too, but we may never know for sure.)
But prosecutors do have discretion, after all, whether to pursue a case or not. (And in the case of the FBI Director, it was not up to him to decide whether or not to prosecute. His words were carefully chosen to give the Attorney General political cover and a reason to go along with Comey’s recommendation.)
Finally, a lot of cases are plea-bargained before a full trial is held. In these cases the prosecutor may over-charge (realizing that the defense team will make a counter-offer for lower charges or sentencing), and the two sides will come to an agreement about what crime was committed – which may be considerably less than what was “actually done” – and for which the defendant agrees to plead guilty and accept the sentence for the lesser crime that is stipulated to.
Judges can also declare mistrials, when one side or the other makes improper statements in front of the jury, or introduces evidence which is clearly prejudicial – and prosecutors may or may not reopen the case. Or a Perry Mason style ending may occur where a completely new person is indicated to have committed the crime (or some other evidence completely and obviously shows that the defendant could not possibly have committed the crime charged), and the case may be rightly dismissed by the judge “with prejudice” – meaning, “This case is sunk, and the charges for this crime may not be redrawn against this defendant.” (Alternatively, if the prosecutor’s case falls apart for some reason, but there’s still a good deal of evidence pointing to guilt, then the judge may dismiss the case “without prejudice”, in which case the prosecutor is still able to rebuild the case, seek new witnesses and re-charge the defendant.)
To specifically respond to one of your comments: The FBI Director does not, cannot and would not (and did not) say that a potential or likely suspect, person of interest or defendant in a criminal case is “not guilty” of a purported crime. He wouldn’t last a day if he did. (On the other hand, we all start the trial with the presumption in favor of the defendant, that he or she is “not guilty until proven so”.) But FBI Directors do not arrive at verdicts.