meaning of "beyond reasonable doubt"

…beyond reasonable doubt
Can you tell me what really means with the above phrase? :oops:
Thank you.

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It is a legal phrase, actually. An overview from Wikipedia:

[i]Beyond reasonable doubt

This is the standard required by the prosecution in most criminal cases within an adversarial system. This means that the proposition being presented by the government must be proven to the extent that there is no “reasonable doubt” in the mind of a reasonable person that the defendant is guilty. There can still be a doubt, but only to the extent that it would not affect a “reasonable person’s” belief that the defendant is guilty. If the doubt that is raised does affect a “reasonable person’s” belief that the defendant is guilty, the jury is not satisfied beyond a “reasonable doubt”. The precise meaning of words such as “reasonable” and “doubt” are usually defined within jurisprudence of the applicable country.[/i]
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