Because all fingerprints are unique. Unless you are a twin and then that is another ball game. They are usually lifted by a type of selotape which is taken back to the lab and again put thru a national and sometimes international database.
Crime scene investigators analyze every aspect of a crime, including the body, the location, fingerprints, fibers, ground, and sometimes air and water. They use special equipment that displays blood stains that may have been scrubbed away.
Fingerprints are left by sweat and oils on our skin, which can transfer onto gloves when they are worn. By examining the fingerprints left on gloves, investigators can potentially identify individuals who have handled them. This can be useful in criminal investigations to link a suspect to a crime scene or piece of evidence.
Crime scene investigators use techniques like powder dusting, cyanoacrylate fuming, or ninhydrin spraying to develop latent fingerprints at a crime scene. They then lift the developed prints using adhesive tape or specialized fingerprint lifting tools for analysis and comparison.
specializes in collecting fingerprints etc from a crime scene or a criminal.
Crime scene investigators document and analyze information found at crime scenes.
A criminal always leaves DNA in the crime scene, and recovering evidence such as fingerprints and DNA is the most interesting thing about crime scenes and crime scene investigators. Forensic investigators can recreate a crime scene using evidence and crime simulation programs.
The police, criminal investigators, forensic scientists, and/or FBI collect physical evidence, which is evidence at the crime scene. They also take photographs at the crime scene and take notes (like to say what time and location the incident happened), and they also do sketches on the crime scene. They draw out two sketches--one is called the rough sketch, which is drawn at the scene. The finished sketch is the sketch drawn after being at the crime scene. Finished sketches include measurements, precise locations, and other things that will help them solve the crime scene.
LATENT fingerprints.
Observation
The crime scene investigators use the biotechnology and genetis technology for solving their case. They collect every sample from the crime scene and perform the laboratory tests on it which gives them clue about what would have happened on the crime scene and then DNA and the fingerprints are used to prove the identity of the person associated with crime scene
Crime Scene Investigators!!
A crime scene investigator collects physical evidence from crime scenes, documents and preserves it for analysis. A crime scene analyst, on the other hand, works in a lab to analyze evidence collected by investigators, such as DNA, fingerprints, and ballistics, to provide conclusions and insights to aid in investigations.