Let's say one juror refused to vote guilty-- would that be a not guilty verdict? If not, how many not guilty votes would be needed? At what point does it become a hung jury?
In criminal matters:
12 votes to convict = conviction.
12 votes to acquit = acquital.
Anything in between is a hung jury.
[Unless you are in Florida and have a 6 person jury then 12 above becomes 6.]
You only need one to hang up the criminal jury. You need at least 3 to tie up a civil jury. It takes only one to block conviction, but in a civil case, it takes at least 3 to block, and that's if the jurisdiction uses the 10 of 12 jurors required.
Given the reasonable doubt standard, finding one juror who will hang it up will not be a problem, unless they just happen to get all the jurors from the OJ trial.