What Does Preponderance of the Evidence Mean in Court?

What Does Preponderance of the Evidence Mean?
Both civil and criminal cases have some legal standards that must be met in order to prove the defendants guilty or liable. 'Preponderance of the evidence' is the standard of proof required in civil cases. This Buzzle post provides a brief insight into this legal concept.
In Santosky v. Kramer, 455 U.S. 745 (1982), the Supreme Court ruled that the 'fair preponderance of the evidence' standard prescribed by 622 (New York Family Court Act ยง 622) violates the due process clause of the Fourteenth Amendment. According to the court, "Before a state may sever completely and irrevocably the rights of parents in their natural child, due process requires that the state support its allegations by at least clear and convincing evidence."
Evidence is one of the most important factors as far as legal disputes are concerned. It comprises materials and assertions that are used to prove the facts related to the case. Evidence can be of different types, such as eyewitness testimony, fingerprints and weapons, documents like contracts, etc. Whatever be the type of evidence, it should be relevant to the facts of the case.
So, evidence is used to prove the claims made by a party to the case. There must be a certain standard of proof for the court to reach a decision in favor of the party that produces the evidence. If both the parties to a case present evidence to prove their claims, the judge or jury has to analyze and weigh the evidence from both sides and give a verdict in favor of the side with a greater weight. What is the standard used for weighing evidence?

Standard of proof is defined as the degree of proof required to establish a case. In civil trials, 'preponderance of the evidence' is the standard rule, whereas in criminal trials, the charges against the accused have to be proved 'beyond a reasonable doubt'. In criminal cases, the prosecution has the initial burden of proof (obligation to prove the claim), which later shifts to the defendant. In civil cases, the plaintiff has to establish his claim, after which the defendant has to produce evidence to prove his part. In both cases, the defendant is not required to prove his part, if the plaintiff/prosecution fails to establish their claims/charges.
Preponderance of the Evidence - Definition
So, preponderance of the evidence is the standard of proof in civil cases. It is also known as balance of probabilities. It is defined as follows: "the greater weight of the evidence required in a civil (non-criminal) lawsuit for the trier of fact (jury or judge without a jury) to decide in favor of one side or the other." The party who brings the lawsuit has to prove his allegations with proper evidence in the form of testimony and exhibits.
The party has to prove that his claims are 'more likely to be true than not'. If the plaintiff fails to prove his claims, the case will be dismissed. But if he produces enough evidence to prove his claims, the defendant has to prove that the plaintiff's claims are not valid. For this purpose, the defendant has to provide strong evidence. Once the judge or jury hears both sides, he has two sets of contradictory evidence that have to be compared to reach a decision.
Meaning and Application of the Concept
The different pieces of evidence from both sides are weighed on the basis of relative importance. While weighing the evidence from both sides, importance is given to the accuracy or truthfulness, rather than the quantum of evidence. In most cases, the party with more convincing evidence wins the case. This standard of proof is called preponderance of the evidence, or which side is more likely to be true. It is not easy to apply this concept to the evidence in a case.
If this standard is converted into a total percentage scale of 100%, the party with 51% of evidence in his favor is said to be met with the standard of preponderance of the evidence.

For example, a party with clear and accurate evidence like a genuine eyewitness, or a murder weapon with the fingerprints of the accused; has a clear edge over the other side with numerous witness testimonies that are vague and hazy. So, a score that ranges from 51 to 100% is considered as preponderance of the evidence. From the viewpoint of a judge, if the probability of the defendant's liability is 51%, it means that the plaintiff has become successful in proving his case. He will win the case, irrespective of the fact that the defendant has 49% of the evidence in his favor. The negligible margin is not a factor that is taken into consideration.
Though this standard of proof is applicable for almost all types of civil litigation, stringent standards are demanded to prove some special cases. In some tort cases, preponderance of the evidence may be considered as a very low standard of proof, to reach a decision. In that case, the standard is often raised to the next higher level - 'clear and convincing evidence' or even 'beyond a reasonable doubt'.