In countries such as the United States, evidence that shows proof "beyond reasonable doubt" is a guiding principle that is needed to convict a person of a crime. However, the term "beyond reasonable doubt" is very difficult to define. Knowing the kinds of evidence that can prove guilt beyond reasonable doubt is necessary. This ensures the understanding of modern-day court proceedings, as well as protection of a person's inalienable rights.
Evidence used against a person accused of a crime should be admissible. Admissible evidence is any evidence that is relevant -- such as evidence that is able to verify facts regarding the accusation. However, relevant evidence may be considered inadmissible in some cases. According to Federal Rules of Evidence, the court can exclude evidence that is prejudiced, confusing or misleading to the jury, or a waste of time. (see reference 2)
Evidence of Character
A person's character may not used as evidence except in two instances. One case is when the present accusation has very specific or unusual elements related to a previous conviction. The second case is when the defence shows that the defendant could not have done the crime based on character. The defending party is therefore telling the jury that character is relevant to the verdict. The prosecution can then make use of character to rebut the defence's portrayal of the accused.
Burden of Proof
According to U.S. Supreme Court Decision 397 U.S. 358 (In re Winship) proof of a criminal charge beyond a reasonable doubt is constitutionally required. This means that burden of proof in a criminal case rests on prosecutors. The stakes are very high in criminal cases, as a defendant risks incarceration and loss of civil liberties. Therefore, prosecutors are under high pressure to prove their version of the facts to be beyond reasonable doubt. Any evidence presented by prosecutors should demonstrate that the defendant committed the crime and that the defendant had a criminal intention when he did.
The Subjectivity of Evidence "Beyond Reasonable Doubt"
What constitutes proof "beyond reasonable doubt" is subjective. James Q. Whitman states that jurors do not understand it clearly. What constitutes legal doubt is not exactly defined, and leads to difficulty in passing judgment. This is because, according to Whitman, proof "beyond reasonable doubt" was understood differently when it was first used. In earlier times, jurors were afraid of damnation secondary to passing judgment. Proof beyond reasonable doubt was understood as a guarantee that jurors can pass judgment without losing salvation. The concept was therefore designed to make pronouncing a verdict easier. Fast forward to contemporary times, the concept has new meaning; it is now understood as evidence that definitely proves an accusation. However, no person can accurately quantify "reasonable doubt" -- hence the degree of subjectivity that still exists in courts today.