Leftist answer:
It all depends.
If the defendant is someone we don’t like then is 100% metaphysical certitude. Anything less and you must convict.
If the defendant is a liberal beloved by the left then it is the slightest doubt in your mind. Even a 1% chance the defendant did not do it is reasonable doubt.
Conservative answer:
You are morally convinced the defendant did NOT do the crime, you must acquit. The evidence must be overwhelming to overcome the presumption of innocence.
That's backwards. If you are NOT morally convinced the defendant did the crime, you must acquit.