Forensic identification is the application of forensic science, or "forensics", and technology to identify specific objects from the trace evidence they leave, often at a crime scene or the scene of an accident. Forensic means "for the courts".
People can be identified by their fingerprints. This assertion is supported by the philosophy of friction ridge identification, which states that friction ridge identification is established through the agreement of friction ridge formations, in sequence, having sufficient uniqueness to individualize.
Friction ridge identification is also governed by four premises or statements of facts:
Friction ridges develop on the fetus in their definitive form prior to birth.
Friction ridges are persistent throughout life except for permanent scarring, disease, or decomposition after death.
Friction ridge paths and the details in small areas of friction ridges are unique and never repeated.
Overall, friction ridge patterns vary within limits which allow for classification.
People can also be identified from traces of their DNA from blood, skin, hair, saliva, and semen by DNA fingerprinting, from their ear print, from their teeth or bite by forensic odontology, from a photograph or a video recording by facial recognition systems, from the video recording of their walk by gait analysis, from an audio recording by voice analysis, from their handwriting by handwriting analysis, from the content of their writings by their writing style (e.g. typical phrases, factual bias, and/or misspellings of words), or from other traces using other biometric techniques. Many methods that are used in forensic science evidence have been proven to be unreliable. A lot of trials have been reviewed and testimony involving mostly microscopic hair comparison, but also bite mark, shoe print, soil, fiber, and fingerprint comparisons have been overturned because forensic analysts have provided invalid testimony at the trial.