Key Pathway – Use of Toolmark Examinations of

Locks and Keys in the Analysis of

Reported Stolen Vehicles & Other Property Losses.

By Richard Pacheco, Michael O’Shaughnessey, M.S.F.S., Antonio Montiero, FL.IL.

The investigative examination of locks has become a debatable issue in regards to the forensic examination of the interior components. The use of microscopes along with acquired knowledge of the working relationship of keys and how they contact the wafers has allowed a forensic locksmith to document the physical presence of a newly made key, as well as picking, tampering or force as having occurred. This examination is useful in determining if the tool marks and striations present on the contact area at which a key contacts the wafer, known as the key pathway, is consistent with the use, and on some occasions the identification of a specific key as having last operated the lock. This physical evidence can assist law enforcement personnel or other interested party in determining whether a given situation has occurred. The examination of keys also may reveal the presence of tool marks that are indicative of a specific key having been used as a guide in a duplication process to create another key.  The technology has evolved into a thorough examination of locks and has now been taken to a level that should be called upon in the future to assist in apprehending a criminal along with proving the innocence of a suspect. The development of the use of the microscopic examination of tool marks in the analysis of locks as a source of information to be used in investigations.

Key pathway, tool marks examinations, forensic science, vehicle theft, insurance fraud The examination of locks to determine if picking or if any other events have occurred has been in existence for some time now. One can find references regarding lock picking and the examination of tool marks made by lock picks and other tools as far back as the mid 70?s (Plumtree 1975). Over time, other advances have been made in the examination of locks. Today the possibility exists as a result of the availability of individuals with specialized training who possess a high degree of knowledge of the internal workings of locks (locksmiths). In some cases it is feasible, in examining pins from a cylinder, to ascertain if it has been picked, and, in some cases, the style pick used to neutralize the cylinder (Glazier 1999), and also in some cases the identification of the actual pick used. The field of investigative locksmiths is expanding and to some degree has also begun to include a new method of examining locks and their internal components. This level of examination has led to a forensic approach to the examination of locks and their internal components in what has become Forensic Locksmithing. Anyone who is involved with this type of examination can attend a class, "Forensic Locksmith" which do Associated Locksmiths of America, Inc. (ALOA), offer.

The examination of locks in order to determine if picking or any other event has occurred has been taken to a higher level of examination, one that includes keys. It is this examination in which not only is a lock being examined, but the keys which operate the lock are also included in the examination. This has become known as a "Key Pathway Analysis". This type of examination, "Key Pathway Analysis" has been conducted on a wide spectrum of locks and keys that are used in many different types of applications, such as residential, commercial, vehicle, boat, padlock, etc. This type of examination is conducted by forensically disassembling the evidence (lock) so as to preserve the integrity of the evidence to be examined; then examining the internal components to observe if any physical evidence is present on them. It should be understood that prior to any disassembly or alteration in any manner, photographs must be taken so as to document the evidence in its original condition. Photographs must also document the process in which the evidence is disassembled. The physical evidence is observable, if present on the evidence to be examined, by the use of a stereoscope. The stereoscope is to be used in conjunction with variable lighting, and the magnification is also variable.

The following is to help the reader understand the basic methodology of the "Key Pathway Analysis". We can begin with examining the lock in order to rule out picking.

Some of the signs to be examined for that would indicate an attempt at picking a lock would be:

• Scratch marks around the face of the lock.
• Scratch marks at the bottom of the keyway, showing where the tension/turning wrench was applied.
• Scratch marks around the upper portion of the keyway, showing where the rake or pick contacted the lock.
• Examination of the lock pins/disc tumblers for tool marks on the lands as result of the rake or pick having contacted.

An external examination of a lock may not reveal damage, however when an internal examination is conducted the damage is then identifiable

Photo 1: Toolmarks as result of picking.

Photo 2: Toolmarks as result of picking.

Photo 3: Toolmarks as result of picking.

Photo 4: Toolmarks as result of picking.

As previously stated the "Key Pathway Analysis" also includes the examination of keys.

A microscopic examination using variable lighting along with variable magnification settings should then be conducted of the keys in order to obtain the following information.

Is there any tool marks from the key having served as a guide to make a duplicate? If they are observed establish the following:

• Are they recent and not over worn
• Are they recent and over worn
• Are they old and over worn

Is the wear on the key examined consistent with one of the following:

• Everyday use
• Moderate use
• Limited use
• Never used

Is the key one of the following:

• Factory original
• After market
• Original Equipment Manufacture

Are there tool marks and striations not consistent with normal key in lock use

Was the key created by one of the following methods:

• Rotary cut
• Clipped/punched
• Code cut
• Impressioned

Is the key a gang style key/Asian gang key/New York style key or other

Is the key damaged in any way such as:

• Broken key bow
• Key blade twisted
• Key blade cracked
• Any other nicks and cuts on the working surface
• Is the factory code stamped on the key blade
• Are there any unique stampings on the bow such as a lock shop name, etc.

The examiner should examine the key for tool marks and striations as a result of a key having served as a guide to make a duplicate, which can be observed on the key as result of the anvil dragging across the cuts and ramps of the key. There are also other tool marks that can be observed on a key that are as result of having been clamped in the jaws of a duplicating machine. Although even if the above physical evidence is observed on a key, the examiner can only document the tool marks and striations observed that are consistent with a duplicate key having been created. If a duplicate key has in fact been created as result of this event, without the suspected duplicate key being present for examination, this can?t be verified.

Photo 5: Toolmarks as result of key having served as a guide to make duplicate key. Tool marks as over worn.

Photo 6: Close up of tool marks observed on key from photo fig 5.

Photo 7: Toolmarks as result of key having served as a guide to make duplicate key. Tool marks are not over worn.

Photo 8: Toolmarks as result of key having served as a guide to make duplicate key.

Photo 9: Toolmarks as result of key having served as a guide to make duplicate key.

It should also be noted that there exists a key, which has become known by the following acronyms: Asian gang key, shaved key, New York style key, and gang key. This type of key is designed to manipulate the lock disc tumblers to the sheer line so that the lock core will rotate to either unlock a door or rotate the ignition lock cylinder to the on/run position. 

The success of the use of a "gang style key" to manipulate the pin/wafer tumblers of a lock can be attributed some of the following. Typically a lock consists of only 4 depths; the more depths make up the lock the more complex it becomes for this type of key to manipulate all the pin/wafer tumblers. It should also be noted that the sequence of the pin/wafer tumblers plays a role; if the lock is celled with the pin/wafers only being 2 or 3 depths, the possibility of manipulation is greater than of a lock that consists of 4 or 6 depths. The wear of the pin/wafer tumblers along with the overall wear level of the lock itself is also a contributing factor; especially the wear level in the wafer deployment channel into which the wafers protrude, thereby preventing the rotation of the lock core to the unlock or start position.

Photo 10: View of "gang style key

The use of this key will leave tool marks on the lock disc tumblers. This key has been primarily used on foreign vehicles such as Toyota, Nissan, etc. and it is successful in mostly the manipulation of locks that contain only 4 depths. It should be understood that it is not restricted to only these types of locks mentioned and therefore mandates to some degree that locks be examined so as to rule out the use of this particular key.

The examiner should commence to examine the pin/wafers along the top and bottom at the outside edges, the wafer deployment channel and the lands of the wafers. The "gang style key" is used similarly to a "jiggle key" whereas it is inserted into the lock and is jiggled side to side and in and out until the lock rotates beyond the locked position. Some of the "gang style keys" are made up of only two depths on one side of the key and being one cut off from the opposing side.

Photographs will document any observations made which are going to be incorporated into a report. It should also be noted that other observations might be made that are not listed above. However if they are deemed pertinent to the case and have aided in coming to a conclusion, they should be documented in a manner that will be of explanatory assistance to the ultimate conclusion.

The examination of the lock pin/wafer tumblers is an intense, systematic and thorough process. After examining the lock and ruling out that it had been picked and that no signs of tampering or force had occurred, at this point it can be stated that only keys of the proper type have been used to operate the lock. The examination of the interior lock components, especially the pin/wafer tumblers, in relation to the keys submitted should be conducted. This is of course after the examination of the keys submitted has been completed.

Some of the objectives in this final examination are an attempt to establish if the pin/wafer tumblers do in fact match the keys. Is the wear level observed on the pin/wafer tumbles consistent with the everyday use of the keys submitted? Are there tool marks and striations present on the lands of the pin/wafer tumblers that are not consistent with those observed on the keys themselves, indicating that another key had been used to operate the lock last? Are there unique tool marks and striations that are a result of a specific key examined, thereby allowing the determination of that key having last been used to operate the lock in question?

The process of examining these components is similar to the process of tool mark/firearm examiners (Moenssens, Starrs, Henderson, Inbau, 1995). The principle identification is that of the key (bullet) being the proper type for the lock (barrel) in question. As the key is inserted into the lock it contacts the pin/wafer tumblers and as result of this action the material on the key erodes a pathway on the pin/wafer tumblers. It is a result of this action which leaves an established wear pattern along with in some instances unique tool marks and striations that correspond to the surface features of a specific key.

A key may possess "class characteristics" in such that it is a key which is cut to operate the lock in question; it also extends to whether the milling of the key is correct for the keyway entrance of the lock. The "unique characteristics" may be that it is a newly made key opposed to a worn key. It may also possess unique features as result of an impact abrasion or other features that are accidental. It should also be understood that tool mark examination has included the examination of drill bits; marks produced by them have been uniquely identified to the bit that made them with positive results (Nichols 1997). This type of examination has included knives, pliers, screwdrivers, etc. This type of process is not new; only the application to keys and locks is relatively new.

The following examples are in order to help you understand the examination of the pin/wafer tumblers. 

If you have a lock that has only been operated by worn keys, then the findings of your examination of the lands on the pin/wafer tumblers should correspond to that type of wear on the keys. With this in mind if the introduction of a newly made key occurred the lands on the pin/wafer tumblers would become altered. The insertion of a newly made key would contact the lands at the very minimum on the outer edges of the key pathway. A newly made key, even after it has been brushed after being created, would possess surface features unlike those of everyday use keys. The examiner would then observe tool marks and striations not consistent with those observed on the worn everyday use keys and would conclude that another key exists that has operated the lock last (if the new key was not present at time of examination).

It should also be understood that even after the insertion of a newly made key into the lock occurs and subsequently a worn key is inserted, the tool marks from the new key will not be eroded completely as result of the use of the worn key. The tool marks will be over worn to some degree as a result of the use of the worn everyday use key. It would require the substantial use of a worn key multiple times to erode the tool marks completely so that an examiner would not be able to observe them.

In another scenario a key may have a "unique characteristics" on the cuts and ramps that leave unique marks on the pin/wafer tumblers. These unique tool marks should be examined in hopes of determining if they are recent along with if they are over worn. The location of the tool mark in relation to the pin/wafer tumblers must be established in order to correlate the possibility that the tool marks and striations observed on the pin/wafer tumblers are as result of this specific key.  If the tool mark is located in the middle of the key the examiner should expect not to observe tool marks on all of the lands on the pin/wafer tumblers only those that would contact the tool mark on the key as it passes through. The "unique characteristics" on a key may result in the determination that the key is not consistent with it having been the last one used in the lock. It may also render the examination inconclusive due to the tool marks observed on the key having obscured the surface features to a degree, which prevents an examiner from conclusively determining that the key was the last key used in the lock.

The following information is a basic outline in performing the actual examination. 

WAFER/PINS EXAMINATION:

A microscopic examination using variable lighting along with variable magnification settings should then be conducted of the wafers/pins in order to obtain the following information.

• Are the wafer lands mechanically damaged
• Are the wafer lands fire damaged
• Are any wafers/pins damaged
• Any signs of picking
• Any signs of tampering
• Any signs of force
• Are there unique tool marks and striations observable on the wafer lands which correspond to similar marks on a key
• How many pathways are observable
• Is there a high level of wear on the wafer lands
• Any tool marks that are non key in the lock related.
• Any signs of a newly made key

Photographs should document any observations made which are going to be incorporated into the report if at all possible. It should also be noted that other observations might be made that are not listed above. However if they are deemed pertinent to the case and have aided in coming to a conclusion, they should be noted along with any observations and document them in a manner that will be of explanatory assistance to the ultimate conclusion.

Photo 11: Damage to ignition lock wafers as result of force turning the ignition cylinder from the lock position without the use of a key of the proper type.

Photo 12: Tool marks not key in lock related.

Photo 13: Tool marks not key in lock related.

Photo 14: Tool marks not key in lock related.

Photo 15: Tool marks as result of a key having been extracted from the ignition lock cylinder while not in the locked position.

Photo 16: Striations as result of a newly made key having been inserted into ignition lock cylinder.

Photo 17: Striations as result of a newly made key having been inserted into the ignition lock cylinder.

Photo 18: View of ignition lock wafer land consistent with only worn keys of the proper type.

AT THIS POINT the examiner has completed an exhaustive, thorough and systematic examination of all the evidence, which now allows the examiner to make a final determination.

The report should reflect what was observed and what was not observed that led to making the determination. The documentation of the examination should be compiled in an in-depth report along with photographs depicting the observations that led the examiner to the conclusion.

The conclusion in the report might be that the examiner observed a level of fire or mechanical damage preventing the examiner from determining the last key used, but he is able to 

Determine that no other means has been used but a key of the proper type.

The conclusion in the report might state that no evidence was observed which indicates that the lock assembly has not been tampered with by picking, force, Asian gang key, etc.

The conclusion in the report might be that the examiner did not observe tool marks and striations on the wafer lands that correspond to any of the keys submitted for examination as having last operated the lock, thereby indicating that another key exist which has not been submitted for examination.

The conclusion in the report might be that the examiner observed tool marks and striations on the wafers/pins that correspond to those observed on a particular key, which enables the identification of that key as having been the last key used to operate the lock.

It should be noted at this time approximately of these types of examinations are assisting in clearing the owner or suspect of suspicions in the case.

Glazier, James H., A New Breed of Locksmith, Locksmith Ledger; February 1999; 92-95.

Nichols, Ronald G., Firearm and tool mark identification Criteria: A review of the Literature, Journal of Forensic Sciences; vol.42, no.3, May 1997; 466-473.

Plumtree, W. G., The Examination of Disc and Pin Tumbler Locks for Tool Marks Made by Lock Picks, Journal of Forensic Sciences; vol.20.no.4, October 1975; 658-667.

Shiles, Donald, Forensics ? The Newest Field in Locksmithing, Locksmith Ledger; April 1998; 85-89.

Starrs, James E., Moenssens, Andre A., Henderson, Carol E., Inbau, Fred E., Firearms Identification and Comparative Micrography, Scientific Evidence in Civil and Criminal Cases; chap.6, 1995;307-398.

Note:

"Key Pathway" and "Keyway Wear Pattern Analysis"

(An article written by permission of E.Lee Griggs titled " Forensic Lock Analysis and Its Relationship to Insurance Fraud Today" appeared in "The HotWire" News Letter in the Fall of 1999 and was later archived in the News Letter section of our Web page. This article disputed the forensics of "Key Pathway Analysis". We have subsequently received an article and information from Richard "Rick" Pacheco, North Eastern Technical Services, P.O. Box 5150, Fall River, Ma 02723, regarding his process. Mr. Pacheco has advised that "Key Pathway Analysis" has been recognized in several courts and has been used by law enforcement in criminal cases. VTI Members Ken Vitty and Glenn Hennings, Sterling Investigative Services, endorse the forensics of "Key Pathway Analysis" finding that it has merit. They have recently been trained and certified in "Key Pathway Analysis" by Rick Pacheco. "Key Pathway Analysis" is a pending trademark of North Eastern Technical Services, P.O. Box 5150, Fall River, Ma 02723 "Keyway Wear Pattern Analysis" is the term used by Ken Vitty and Glenn Hennings to describe their process and is very similar to the process used by Mr. Pacheco.

Mr. Gregg?s article has been removed from the website because it refers to "Key Pathway Analysis" a pending trademark without permission, and provides some information that is questionable and NJ VTI has not been provided supporting documentation.

Mr. Pacheco has graciously provided NJ VTI with his article on "Key Pathway Analysis". This article is very detailed and contains numerous color photographs, which the HotWire would not do justice in it?s current format. Only the first three paragraphs are included in the News Letter, the full article with color photographs is posted here in the Member?s Only Section of our website - Hot Wire Editors)