Age Determination-Case Report

(The following article was originally published in the April 1994 issue of Fingerprint Whorld, the publication of the Fingerprint Society. Thank you Dennis Uyeda/CAL-DOJ for this contribution.)

by Sgt. DEAN GREENLEES

South Australian Fingerprint Bureau, Adelaide

On Saturday 29th of August, 1992, one of our Crime Scene Examiners attended the scene of a breaking at a home unit in the Adelaide suburb of Woodville. An examination was made at three possible points of entry, with the development of two full hand prints on the outside glass surface of an aluminum (sic) sliding window. These impressions were photographed at the scene by the Crime Scene technician.

The negatives of these impressions were packaged and submitted to the Fingerprint Bureau, where they were subjected to a search on the Automated Fingerprint Identification System. As a result of the search, the impressions were positively identified as belonging to a Police Officer. The necessary paper work was prepared and dispatched (sic) to the appropriate authority for investigation.

During the following investigation, the officer concerned stated he had never been to the premises leaving him a suspect for the unit break and larceny. Sometime over the next couple of days, the officer stated that he recalled attending at the unit some two years ago, in response to a call. The elderly owner had inadvertently locked himself out of the premises. The officer stated that he had pushed against all the windows of the unit in an attempt to gain entry for the owner. This response required further investigation from the Departments' Internal Investigation Branch. The owner of the unit, who was then residing at a Nursing Home, was contacted and stated that he had never cleaned the windows.

On Monday 28th of September, 1992, three members of the South Australian Fingerprint Bureau attended the unit. A request had been made to attempt to age the fingerprint impressions left on the glass. An examination of the impressions, which still had not been cleaned since the breaking, was conducted and observations were also made of the position of the window in relation to the outside elements. The impressions that had been developed were as the photographs had depicted. Good quality for powder development, showing no signs of fragmentation of ridge detail, indicating little or no breakdown of the matter deposited on the pane of glass upon contact with the fingers.

The position, under an open ended car-port, was exposed to all the weather elements including hot northerly winds, except for rain or moisture from dew. Where the glass had not been powdered, it showed signs of a dirty film over the outside surface, consistent with it not being cleaned for some time.

All observations made at the scene, led to the belief that the fingerprints were unlikely to have been left there for an extended period of time, although it was impossible to know whether the original deposit on the window was purely perspiration or contaminated with other oils making the breakdown process longer.

Photographs of the developed impressions were also shown to a scientist from the South Australian Forensic Science Centre, who has had considerable research experience in latent fingerprints. He came to the same conclusions as the fingerprint experts, that it was unlikely the deposit was two years old as there was (sic) no signs of breakdown or fragmentation of the ridges.

Whilst further investigations were being carried out by Internal Investigation, the pane of glass was removed from the window by fingerprint experts and taken to the Bureau for further examination. The entire pane of glass was dusted with powder and a number of other fingerprint impressions were located. Internal Investigations advised that they had ascertained from records that the officer did attend the unit in August, 1990, to assist the owner in gaining entry. The records showed that the officer was accompanied at the time by a cadet, who when questioned could remember the incident and stated that he also tried all the windows in an attempt to gain entry.

With this information all the fingerprint impressions now developed on the pane of glass were examined, with more impressions of the officer concerned being identified, and, to our surprise, fingerprint impressions on the pane of glass were also identified as the cadet (sic). These fingerprints showed the same quality and powder adherence as those developed at the scene.

Both the officer and the cadet have not worked together since that event, drawing the conclusion that the impressions were deposited on the window in August, 1990. There they remained, undisturbed and undetected for a period of two years (through two summers with temperatures of 40o C and two winters with temperatures dropping to 1o C or 2o C: high humidity and low humidity) retaining sufficient moisture and form to be developed in August, 1992, without any tell tale signs of their age.

The question of `age determination' in latent prints is one that will be talked about for many years and I agree with the concluding statement in Charles Midkiff's article, that speculation of the time a latent print was placed is fraught with danger.

I have included a few photographs showing the quality of the fingerprint impressions developed and the number located on the window.

(Editor -- Unfortunately, the photographs in the original article would not reproduce satisfactorily in this reprint. In the original article they illustrated that the prints were extremely clear and distinct. I haven't located the "Charles Midkiff's" article to review for possible reprinting, but my search led me to another fine article from the Fingerprint Society "Latent Fingerprints - One Year Later", another testimony of the dangers of speculation, and it is reprinted on the next page of this issue of THE PRINT. Enjoy and be warned of the dangers in the speculation of when a print was placed.)

This article was reprinted in "THE PRINT" 10(7), August 1994, pp 4-5
and has been obtained from the online library provided by the

Southern California Association of Fingerprint Officers
www.scafo.org