CALIFORNIA IAI STATISTICAL COMMITTEE REPORT 2001 Summation reported in the July 2002 CSDIAI Identification Digest.

CALIFORNIA-DOJ CENTRAL SITE  LATENT DATABASE FOR THE YEAR OF 2000:

DATABASE FINGERS - 42,391,980

Latents searched  - 125,732

Average candidate list - 10

This report is more defining than the simple reported numbers.  The California database is comprised of NEC minutiae extraction based upon an algorithm that emulates the way the human makes a fingerprint comparison.  The algorithm not only plots the type and directionality of level two minutia on an x-y coordinate.  It also counts the number of intervening ridges between minutiae.

ANALYSIS:

The historical statistical breakdown of fingerprint pattern types applied to the total number of fingers in this latent searchable fingerprint database would be as follows:

FINGERS -                 42,391,980

Avg. 60% loop           25,435,188

Avg. 35% whorl        14,837,193

Avg. 5% arch                2,119,599

The historical statistical breakdown of fingerprint pattern types applied to the total latent searches would be as follows:

LATENTS SEARCHED        125,732

Avg. 60% loop                         75,439

Avg. 35% whorl                       44,006

Avg. 5% arch                              6,286

The total number of fingers searched would be somewhere between only searching single latent pattern calls to total pattern reference. This would equate as follows:

No reference  2,585,054,462,004 

(75,439 x 25,435,188) + (44,006 x 14,837,193) + (6,286 x 2,119,599)

(125,732 x 42,391,980)

Between 2.5 and 5.3 trillion individual latent searches were made by California DOJ in the year 2000.  The computerized searches utilized an algorithm that emulates how a human would make a level two comparison of minutia type, flow, and direction in an x-y coordinate related to the pattern core, counting the number of intervening ridges between the minutiae.

The 2.5-5.3 trillion searches provided list of candidates of the ten fingerprints with the closest agreement, to a human for Analysis, Comparison, and Evaluation.  For the 125,732 latents searched by California DOJ, a human latent fingerprint analyst examined the top 1,257,320 candidates.  These examinations found no two different fingerprints that contained twelve or more level two Galton detail of the same type, direction, ridge flow, x-y axis location, and ridge count spatial relationship.  No where near twelve level two Galton detail were found. 

The past limited statistical models, as well as Dr. Edmond Locard's  tripartite rule, have been validated by the California DOJ latent database, supporting quantifiable thresholds for friction ridge individualization.