What Is Admissible Evidence?

In the legal world, evidence is a crucial concept. Evidence pertains to any material that provides insight into the truth of a matter in court. While this sounds straightforward, the concept of evidence in practice is complex. The issue of admissibility comes into play because the justice system aims for impartiality and due process, or the presumption of a defendant’s innocence until proven guilty. Generally, there are four types of evidence that may come into play in any given legal case:

  • Demonstrative evidence . Any evidence used to demonstrate facts of the case is demonstrative evidence. This could include photographs, x-rays, charts, maps, diagrams, forensic animations, or any other visual evidence that pertains to the case at hand and provides context for the situation in question.
  • Documentary evidence . This includes any documentation pertaining to the case. Documentary evidence can include wills, trusts, estates, invoices, records, receipts, or any other documentation that provides context for the case.
  • Real evidence . Any tangible items related to the matter at hand could be real evidence. These items are things jurors can touch and feel to gain a better understanding of the case, and they can include things like murder weapons, narcotics, articles of clothing, personal belongings, or fingerprints.
  • Testimonial evidence . Testimonial evidence is the spoken evidence that witnesses and key figures provide in a case. Once a witness takes the stand, he or she will answer questions from both sides about his or her knowledge of the matter at hand. The issue of admissibility most often comes into play with testimonial evidence due to the inherently flawed nature of human memory and the possibility of bias.


For any type of evidence to qualify as admissible, it must meet three criteria: It must be relevant, material, and competent. To be relevant, it must prove or disprove a claim or fact of the case. To be material, the evidence must prove or disprove a claim in the case. The competency of a piece of evidence hinges on the reliability of kept records, the truthfulness of a witness’s statements, or a witness’s demonstrated ability to provide reliable testimony.

Some evidence will require expert testimony to qualify as admissible in a case. For example, the average person would not know how to handle or interpret DNA evidence, and a medical expert may be necessary to help prove the evidence’s validity.


Either side of a legal battle may argue that a piece of evidence is inadmissible under various circumstances. A piece of documentary evidence found to have been stored in an unreliable location or using outdated methods may be inadmissible due to its unreliability. A piece of testimony may be inadmissible because it is hearsay or statements heard outside of court and not under oath. A piece of real evidence that has been mishandled, mislabeled, or incorrectly stored may be compromised and therefore no longer be useful to the case.

Generally, judges exclude any piece of evidence that does not meet the three criteria of being relevant, material, and competent as inadmissible. While there are some exceptions, an experienced attorney is the best resource for determining whether a piece of evidence will be admissible at trial.