What is the current state of the law on the meaning of proof beyond a reasonable doubt?

The presumption of innocence and the concomitant burden on the prosecution to prove guilt beyond a reasonable doubt represent the twin core values upon which our criminal justice system is built. Many well-meaning judges and prosecutors have tinkered with explanations of the meaning of proof beyond a reasonable doubt without success and appellate courts have admonished them to restrain their creativity and faithfully abide by the now well-accepted instruction. (See, e.g., People v. Centeno

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