The Florida standard jury instructions defining reasonable doubt is as follows: Whenever the words reasonable doubt are used you must consider the following: A reasonable doubt is not a mere possible doubt, a speculative, imaginary or forced doubt. Such a doubt must not influence you to return a verdict of not guilty if you have an abiding conviction of guilt. On the other hand, if, after carefully considering, comparing and weighing all the evidence, there is not an abiding conviction of guilt, or
if, having a conviction, it is one which is not stable but one which wavers and vacillates, then the charge is not proved beyond every reasonable doubt and you must find the defendant not guilty because the doubt is reasonable. It is to the evidence introduced in this trial, and to it alone, that you are to look for that proof. A reasonable doubt as to the guilt of the defendant may arise from the evidence, conflict in the evidence or the lack of evidence. If you have a reasonable doubt, you should find the defendant not guilty. If you have no reasonable doubt, you should find the defendant guilty.
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