Evidence is presented to prove facts. Evidence can be materials or witnesses. Facts can be represented in natural language sentences, statements, assertions, or logical propositions. The proof is evidence accepted to believe facts are true or probably true. Investigation is the process of evidence identification, collection, preservation, analysis, review, processing, production, and presentation; investigation involving forensics or scientific knowledge is known as forensic investigation.
The following definitions come from https://dictionary.law.com.
n. confirmation of a fact by evidence.
In a trial, proof is what the trier of the fact (jury or judge without a jury) needs to become satisfied that there is “a preponderance of the evidence” in civil (non-criminal) cases and the defendant is guilty “beyond a reasonable doubt” in criminal prosecutions. However, each alleged fact must be proved separately, as must all the facts necessary to reach a judgment for the plaintiff (the person filing a lawsuit) or for the prosecution (the “people” or “state” represented by the prosecutor). The defendants in both civil suits and criminal trials need not provide absolute “proof” of non-responsibility in a civil case or innocence (in a criminal case), since the burden is on the plaintiff or prosecution to prove their cases (or prove the person guilty).
burden of proof
n. the requirement that the plaintiff (the party bringing a civil lawsuit) show by a “preponderance of evidence” or “weight of evidence” that all the facts necessary to win a judgment are presented and are probably true.
In a criminal trial the burden of proof required of the prosecutor is to prove the guilt of the accused “beyond a reasonable doubt,” a much more difficult task.
Unless there is a complete failure to present substantial evidence of a vital fact (usually called an “element of the cause of action”), the ultimate decision as to whether the plaintiff has met his/her burden of proof rests with the jury or the judge if there is no jury.
However, the burden of proof is not always on the plaintiff. In some issues it may shift to the defendant if he/she raises a factual issue in defense, such as a claim that he/she was not the registered owner of the car that hit the plaintiff, so the defendant has the burden to prove that defense. If at the close of the plaintiff’s presentation he/she has not produced any evidence on a necessary fact (e.g. any evidence of damage) then the case may be dismissed without the defendant having to put on any evidence.
beyond a reasonable doubt
adj. part of jury instructions in all criminal trials, in which the jurors are told that they can only find the defendant guilty if they are convinced “beyond a reasonable doubt” of his or her guilt.
Sometimes referred to as “to a moral certainty,” the phrase is fraught with uncertainty as to meaning, but try: “you better be damned sure.” By comparison it is meant to be a tougher standard than “preponderance of the evidence,” used as a test to give judgment to a plaintiff in a civil (non-criminal) case.
preponderance of the evidence
n. 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.
This preponderance is based on the more convincing evidence and its probable truth or accuracy, and not on the amount of evidence. Thus, one clearly knowledgeable witness may provide a preponderance of evidence over a dozen witnesses with hazy testimony, or a signed agreement with definite terms may outweigh opinions or speculation about what the parties intended.
Preponderance of the evidence is required in a civil case and is contrasted with “beyond a reasonable doubt,” which is the more severe test of evidence required to convict in a criminal trial. No matter what the definition stated in various legal opinions, the meaning is somewhat subjective.
RULE 133: Weight and Sufficiency of Evidence
Section1. Preponderance of evidence, how determined.
— In civil cases, the party having burden of proof must establish his case by a preponderance of evidence. In determining where the preponderance or superior weight of evidence on the issues involved lies, the court may consider all the facts and circumstances of the case, the witnesses’ manner of testifying, their intelligence, their means and opportunity of knowing the facts to which there are testifying, the nature of the facts to which they testify, the probability or improbability of their testimony, their interest or want of interest, and also their personal credibility so far as the same may legitimately appear upon the trial. The court may also consider the number of witnesses, though the preponderance is not necessarily with the greater number. (1a)
Section 2. Proof beyond reasonable doubt.
— In a criminal case, the accused is entitled to an acquittal, unless his guilt is shown beyond reasonable doubt. Proof beyond reasonable doubt does not mean such a degree of proof, excluding possibility of error, produces absolute certainly. Moral certainly only is required, or that degree of proof which produces conviction in an unprejudiced mind. (2a)Source: The Lawphil project