Maybe. Is one print in blood and one in a different-looking substance like sebaceous sweat? Are the prints oriented differently so that one can follow the ridge flow of each separately? Are there areas that can be used for identification outside of the overlapping area(s)? Are the prints left in a raised material (blood or whatever) that can be lit from an angle showing the top print only? Did the murder apply sufficient pressure that the underlying print is not a problem? (For example, a print in clay pressed hard enough will flatten the previous print so it is no longer interfering.)
I do not think that there is really a purpose of making fingerprints not on purpose anyways. Fingerprints are mostly made because of the oil of our fingers. Answer 2: Assuming you mean why is is that some agencies take your fingerprint (police, CBP...). Its because each individual has its own unique fingerprint mening that is you have someone fingerprint you can identify him. In most crimes fingerprints are left behind and these can be collected and matched with fingerprints on database to identify the suspect.
Latent fingerprint examiners are people who look at fingerprints left on a crime scene. Also register, search, analyze, and identify fingerprints in the Automated Fingerprint Identification System (AFIS). They also record criminal history and provides expert witness testimonies in court. They view animated or hard copies of fingerprints and they also prepare the print for computer entry. They also enhance the fingerprint with the computer. They also have to prepare displays of the latent fingerprint for testimonies.
By adhering to the oils left by a finger.
Plastic
Water
There is only one Fingerprint, which you get from the wine glass of a BAD bigwig at the BAD Bistro. (when you use the fingerprint, slide it left and right at the door) (see related question)
One advantage of using a fingerprint door lock is that there is no point of keeping a key that can be unintentionally left at anywhere. Moreover, fingerprint is very specific for each person, therefore using a fingerprint door lock will increase the safety for the house.
Added: Forensic dentistry can be utilized to identify things such as bite marks left on a victims body to identifying deceased person's from their dental records.
A Crow Left of the Murder... was created on -20-11-10.
Everyone has a different design on their fingers and you have natural oil, also called sebrum, on your skin so a fingerprint is the oil left on what you touched in the design of your unique finger.
Wear a pair of glove to touch the thing a second time ,then you can clean up the residue fingerprint powder
Basically, a fingerprint left on a surface is caused because: Oils form on sweat glands in our fingers, collecting on ridges of a fingerprint. After touching something, the oils and other materials previously on the ridges are left behind on the surface you just touched. I hope that helps.