Evidence is anything that tends to prove or disprove a material or relevant fact alleged in a lawsuit or other legal proceeding. Witness testimony, documents, contracts, email messages, photographs, medical bills, video images, and voice recordings are common pieces of evidence.
In Kansas, evidence is governed by the Kansas Rules of Evidence, which are similar to the Federal Rules of Evidence. These rules determine what is considered admissible evidence in court. Evidence must be relevant to the facts of the case, meaning it should have any tendency to make a fact more or less probable than it would be without the evidence. The types of evidence mentioned, such as witness testimony, documents, contracts, email messages, photographs, medical bills, video images, and voice recordings, can all be admissible if they are relevant and not excluded by other rules. For example, hearsay is generally not admissible unless it falls under one of the many exceptions. Additionally, evidence must be authenticated before it can be admitted, which means there must be a demonstration that the evidence is what it purports to be. The Kansas rules also address the admissibility of expert testimony, character evidence, and the balancing of probative value against potential prejudicial impact.