I served as jury foreperson once. Felony drunk driving (which meant the person had to also have a fairly recent drunk driving conviction on their record because I knew the law in the state). Guy was clearly guilty as charged, zero doubt of any kind in my mind, reasonable or otherwise. But the prosecuting attorneys did such a poor job presenting a case that had been equally poorly investigated by the Sheriff's office there was no way I was going to vote "guilty." Witnesses contradicted each other on key elements, they tried to paint the guy as having an affair on his wife (as if that had ANYTHING to do with what he was on trial for) and it was clear that at least one of the police officers testified untruthfully. No one was hurt in the accident the defendent had (well, no people, he hit and killed a doe), he just totaled his vehicle. And the kicker, one of the other jurors had lost a brother in a drunk driving accident and clearly that should have disqualified her from serving on that particular jury.
We were either 9-3 or 10-2 to convict on the first ballot before we started to discuss all the ridiculousness of this trial. The trial itself was brief, less than a full day. We deliberated for the rest of that day, maybe 90 minutes, and then all day the next day. Little by little we convinced people that in our system it isn't really just guilt that needs to drive a verdict, but did the state PROVE GUILT BEYOND REASONABLE DOUBT. Eventually my side won out and we acquitted the guy.
Afterwards as some of us were waiting to get out jury pay (like $12 a day) the defendent comes over and tries to thank us for "seeing the truth." We told him to get bent, and that he was clearly guilty and needed help before he killed himself, or worse yet, someone else. We said you are basically getting a mostly undeserved second chance, and the only thing you should be doing right now is finding an AA meeting and finally admitting to yourself you were probably a hopeless drunk and its time to take responsibilty for it. I don't know if I would have felt the same way if the guy was on trial for being a mass murderer, or if he had run over kids in a crosswalk while drunk, but at the time it sure seemed like the right thing to do.