FWIW, I was on a jury for the first and (so far) only time, about 2 years ago. It wasn't a big, flashy murder or rape case, just a guy being accused of breaking into a cop car and stealing a flashlight and a handheld radio. But, I found that the other jurors, by and large, took the "innocent until proven guilty" thing VERY seriously. I know that most of us thought he was "probably" guilty, but in the end, we actually acquitted him on all charges because we didn't believe the State had proven he was guilty "beyond a reasonable doubt".
Granted it's just one anecdote about one jury on one case in North Carolina, but this jury was not prejudiced against the "criminal" from the start. And, if anything, by the end, most of us were biased against the State for being (or appearing to be) some combination of: incompetent (the investigator from the Sheriff's department), abusive / a plain dick ( the prosecutor), and/or dishonest (the cop who had his car broken into).
Granted it's just one anecdote about one jury on one case in North Carolina, but this jury was not prejudiced against the "criminal" from the start. And, if anything, by the end, most of us were biased against the State for being (or appearing to be) some combination of: incompetent (the investigator from the Sheriff's department), abusive / a plain dick ( the prosecutor), and/or dishonest (the cop who had his car broken into).