I'm not a lawyer but I was on the other side as a Law Enforcement Officer and in the end the jury can do whatever they wish. If the guy is as guilty as sin and the evidence proves it but the jury decides to acquit then that's what they can do. if one juror will not listen to reason and is pig headed for one reason or another unless you can prove he was compromised you just have a hung jury and retry the case.

The reason why we have citizen jurors and not a tribunal of sorts is so the jury can apply common sense and reason and compassion to deliver a fair verdict for all parties concerned. remember our system in the U.S is based on the premise that 100 guilty people go free rather than convict 1 innocent man. Does that work? I'm not so sure but at least we don't have a system where the accused is presumed guilty and must prove his innocence.