Latent Fingerprint Fabrication

Pat A. Wertheim; Director of Training
Forensic Identification Training Seminars, Ltd.
1230 Hoyt St.
SE Salem, Or 97302-2121
1-888-235-1230 FAX 1-800-588-0399

ABSTRACT: Types of latent print fabrication are discussed briefly. Concerns are raised over tow issues. First, examiners should be aware of the clues to fabrication in order to expose the dishonest police personnel who would fabricate such evidence. Second, examiners should use conclusive methods of documentation to prevent a disruptive challenge to the validity of their latent print evidence in court.

Cases of fabrication of latent print evidence by police officers and identification technicians occur frequently enough in the United States to make publicity of these cases a threat to the credibility of honest latent print and crime scene professionals. In addition, latent print examiners who compare latent prints developed by others run the risk of receiving submissions of fabricated evidence and being drawn unsuspectingly into such cases. Therefore, conscientious examiners need to be alert to the signs of fabrication in latent print evidence submitted by others, and they need to follow procedures in their own cases to document absolutely the authenticity of their latent prints in order to preclude the charge of fabrication against their legitimate evidence.

A review of the literature published on the topics of latent print forgery and fabrication shows two unrelated types of false evidence. The most widely accepted definitions were those given by George Bonebrake in his 1976 presentation to the International Association for Identification.1 A “forged” latent print is one which actually exists on a surface, but was not left by the person whose fingerprint it represents. A “fabricated” latent print is a representation of print that never existed on the surface from which it purportedly came.

By considering these definitions in their practical meanings, a forged print would be a latent planted at a crime scene by the true criminal in order to fool the police, while a fabricated print is fabricated evidence produced by a police employee in order to bolster a case or frame a person. In those terms, forgery of latent print evidence is virtually nonexistent. Fabrication occurs disgustingly often. In considering fabrication, two issues arise; first, how to protect yourself from getting drawn into a fabrication scheme perpetrated by a dishonest police employee; and second, how to protect your evidence from an unsubstantiated charge of fabrication by a defense attorney trying to get his client off the hook.

There are three common methods used by dishonest police employee to fabricate latent print evidence: 1) a lift from an inked print. 2) a mislabeled lift, 3) a staged photograph.2 One thing these fabricated latents frequently have in common is that they are “perfect” prints. In other words, a fabricator usually prepares a print so clear nobody could fail to see the identification. I addition to that, each of the three methods leaves tale clues, to a greater or lesser degree.

Consider the lift from an inked print. Clues to this fabrication are numerous. Ink is a different shade of black than fingerprint powder. Lifted inked prints are usually the fully rolled prints, a phenomenon virtually impossible in real latent print work. Lifts from inked prints usually include fibers and microscopic fiber marks.

Next, consider mislabeled lifts. these are often the hardest of the fabrications to detect. The most reliable methods of detection is by a close inspection of background noise. Each type of surface leaves a trademark background noise, and frequently, fabricators fail to take this into account. A mislabeled latent may also reflect an orientation inconsistent with normal handling. However, a clever fabricator may be able to make a mislabeled latent match expectations of genuineness to such a high degree that it would be virtually undetectable.

The staged photograph is the third type of fabrication. These photographs are usually taken slightly out of focus in an attempt to hide details which would disclose the fabrication. Or, such a photograph may be over or under-exposed. Strange lines or shadows may be present. The photographs may also contain stray images not expected on the surface from which the latent purportedly came, or background noise may not be consistent with the surface claimed.

Anytime you have a nagging suspicion about a latent print submitted by another person, back off and take a hard look at it. You need not be suspicious of every latent which crosses your desk, but pay strict attention to those that arouse even the slightest feeling that something is not right. Ask for the opinions of other examiners you trust. Do a critical analysis of the latent to determine what is wrong with the way it looks.

In no case, however, should you report the origin of a latent print you did not personally see on the surface. For example, unless you actually lifted the latent print from the rear view mirror yourself, you should refer to, “The latent print lift labeled as coming from the rear view mirror”, and not, “the latent print from the rear view mirror.”

For latents you do develop, it is important to realize that a defense attorney may still attack the print, and you personally, on the issue of fabrication. The key to surviving such an attack is good documentation of your latent print evidence. Not all of the following methods are necessary, but the more you use, the stronger your documentation.3

  • Photography. This is the most time-honored method of latent print documentation, and perhaps the best. By photographing your latents before lifting them, it is hard to argue their origin.

  • Notes. Good crime scene and laboratory notes are used to record every surface examined, every method used, and every result obtained.

  • Witnesses. If a victim, complainant, or other officer is watching you develop the latent prints, have them initial the lifts and the evidence. They will then be able to testify as to the origin of the latent.

  • Background noise. Background noise is very helpful in establishing the origin of the latent. Create your own background noise. One excellent way to do this is to use a ballpoint pen. Mark a curved line around the latent, the initial and date the latent next to the line. Re-powder the markings. When you lift, the powder will come up on the lift but the ink will remain on the surface as proof of the origin of the latent.

  • Prenumberd lift cards. By using a card with a unique number and recording the numbers in your notes, you make it virtually impossible to insert or swap latents at a later date. Each latent then has in effect a serial number which prevents alteration.

  • Preserve the latent. Fuming preserves a latent print. If the latent is still clearly visible on the evidence when introduced in court, it becomes impossible for fabrication to become an issue.

  • Log book. The use of a latent print log book helps document latent prints. Each case entry should be made as soon as the latents are lifted or brought back to the office from the scene. The entry should contain sufficient information to adequately document every lift.

  • Reviews and audits. There should be both supervisory and technical reviews of the notes and reports in each case file, once completed. Such a review should include an inspection of the lifts. In addition, their should be a random inspection and evaluation of a few cases by an outside inspector on a periodical basis. More and more, these procedures are being accepted as proper quality control measures.

To adopt all the foregoing methods of documentation may be overkill. But in a hard fought court case, some combination of them would certainly help you establish the validity of your evidence. Inn the absence of any documentation at all, a skeptical jury may disregard valuable latent fingerprint evidence, believing that the defense attorney’s argument of fabrication raised a reasonable doubt.

To ignore the problem of fabrication of latent fingerprint evidence allows fabricators to flourish. To avoid innocently being caught up in a fabrication scheme one must be aware of the signs of fabrication, and must report and testify to only those things within the realm of personal knowledge. To survive an attack in court alleging fabrication, documentation of your latent print evidence must be so strong as to preclude the possibility of fabrication.


  1. Bonebrake, George C. “Fabricating Fingerprint Evidence” Identification News, 26(10), 1976

  2. Wertheim, Pat A. “Detection of Forged and Fabricated Fingerprints.” Journal of Forensic Identification, 44(6), 1994

  3. Wertheim, Pat A. “Integrity Assurance: Policies and Procedures to Prevent Fabrication of Latent Print Evidence.” Proceedings of the International Symposium on Fingerprint Detection and Identification, June 26-30, 1995, Ne’urim, Israel, Israel National Police.