Describe the presumption of innocence and how it affects a criminal trial

Question

What purpose does it serve in the criminal law system?

Answer 1

In criminal trials, the defendant is innocent until proven guilty. The prosecutor bears the burden of proving the defendant guilty as charged. Defendants do not have to prove that they did not commit the offenses. In fact, they are not required to present any evidence whatsoever to counter the state's accusations (although clearly it might be in their best interests to present a defense). Even a defendant who actually committed the crime is innocent in the eyes of the law unless the prosecutor can present sufficient evidence to convince the jury or judge of the defendant's guilt.
Not only does the state bear the burden of proving the defendant guilty, but it also is held to a very high standard of proof. In criminal cases the prosecution must prove its case "beyond a reasonable doubt." It is not enough for the jury (or judge) to think that the defendant is probably guilty; the members of the jury must be firmly convinced of the defendant's guilt. The jurors receive instructions such as, "If you think there is a real possibility that he is not guilty, you must give him the benefit of the doubt and find him not guilty." The presumption of innocence and the high burden of proof are designed to protect the individual from the state.