Physical evidence

Real evidence, physical evidence, or material evidence is any material object that plays some role in the matter that gave rise to the litigation, introduced in a trial, intended to prove a fact in issue based on the object's demonstrable physical characteristics.

Examples include the written contract, the defective part or defective product, the murder weapon, and the gloves used by an alleged murderer.

Trace evidence, such as fingerprints, glove prints and firearm residue, is also a type of real evidence. Real evidence is usually reported upon by an expert witness with appropriate qualifications to give an opinion. This normally means a forensic scientist or one qualified in forensic engineering.

In a murder trial for example (or a civil trial for assault), the physical evidence might include biological evidence such as DNA left by the attacker on the victim's body, the body itself, the weapon used, pieces of carpet spattered with blood, or casts of footprints or tire prints found at the scene of the crime.

Admission of real evidence requires authentication, demonstration of relevance, and a showing that the object is in "the same or substantially the same condition" now as it was on the relevant date. An object of real evidence is authenticated through witness statements or by circumstantial evidence called the chain of custody.

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