The interviews are subjective. If you give off a bad vibe they may ask for more information or question you more deeply. It's not a machine that grades you but a human.
From your explanation I feel that SOMETHING happened, acquitted or not. If you say "I got arrested, it was a big mistake, it's all clear" I'd tend to believe that. But you ramble on and on and on, just like a person trying for a quick adjudication and hoping that I agree with you before I have time to think about your compete story.
Maybe it is a language barrier. Maybe you are hiding something. Maybe you have a different way of communicating when you are nervous.
But you cannot lie to the interviewers. They hear hundreds of stories a day and can pick out the one liar who stands out from all the rest. Your attitude and explanation, from my point of view, warrant further investigation. If it is all truly an egregious error, be quiet and let the paperwork do the talking.
