Gathering DNA Evidence
Physical and Biological Evidence

Physical evidence is any tangible object that can connect an offender to a crime scene. Biological evidence, which contains DNA, is a type of physical evidence. However, biological evidence is not always visible to the naked eye. DNA testing has expanded the types of useful biological evidence. All biological evidence found at crime scenes can be subjected to DNA testing. Samples such as feces and vomit can be tested, but may not be routinely accepted by laboratories for testing.

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