Microstamping Part 2

The ear­lier study from UC Davis I had in this blog has recently been peer reviewed, and is sched­uled to be pub­lished in a future issue of the Association of Firearm and Toolmark Examiners (AFTE) Journal. Since I am a sub­scriber to that jour­nal, I will be sure to let you all know when/if it sees daylight.

An update to the orig­i­nal UC Davis arti­cle is located here.

The actual UC Davis report is located here.

It’s inter­est­ing to note that a fact sheet from NanoMark Technologies (with copy­right infor­ma­tion from ID Dynamics — where the fir­ing pins in the UC Davis stud­ies were obtained) responded to one of the prob­lems with the tech­nol­ogy described by the UC Davis research. The prob­lem where a fir­ing pin might strike the primer twice — not exactly in the same posi­tion (some­times called fir­ing pin bounce, and it is not uncom­mon) — result­ing in a dou­ble impres­sion of the code which is not legible.

The crit­i­cism from NanoMark states that the equip­ment used to view the fir­ing pin impres­sion code was opti­cal microscopy. This is the stan­dard tech­nique used in foren­sic labs around the world for this type of exam­i­na­tion. NanoMark showed images of scan­ning elec­tron microscopy where the “illeg­i­ble” dou­ble strike codes were in fact readable.

One of the cited ben­e­fits of the micro­stamp­ing tech­nol­ogy was the lower cost, and not need­ing a foren­sic sci­en­tist to help track firearm usage based on recov­ered crime scene evi­dence. The lower cost is when com­pared to a dig­i­tal pho­to­graph data­base of highly vari­able loca­tions on a fired car­tridge cas­ing, some­times referred to as a “Ballistic Database” or “Ballistic Imaging” or “Ballistic Fingerprints”. There is a real cost of equip­ment for the cur­rent sys­tem, as well as train­ing peo­ple to input images into the sys­tem cor­rectly, and ulti­mately in order to con­firm a “match” it requires a trained foren­sic firearm exam­iner to look at two exhibits under a spe­cial­ized opti­cal microscope.

If we remem­ber from the orig­i­nal Davis study, it was noted that the code to read the “redun­dant radial” and “gear codes” was not avail­able for researchers to deter­mine if in those tool­marks repro­duced with suf­fi­cient detail to be usable. Without access to that patented infor­ma­tion, those extra codes are reduced to unknown pat­terns in the fir­ing pin impres­sion, and it would require a trained foren­sic firearm exam­iner to look at two exhibits under a spe­cial­ized opti­cal micro­scope to deter­mine if they had the same source.

A scan­ning elec­tron micro­scope is not equip­ment every firearm lab has access to. Not even every crime lab in the coun­try has one, and those labs that do, prob­a­bly do not have suf­fi­cient quan­tity of them to start using them in every firearm related case that floods through their doors. The micro­stamp­ing tech­nol­ogy would ulti­mately result in lab­o­ra­to­ries hav­ing to pur­chase expen­sive scan­ning elec­tron micro­scopes, as com­pared to the cur­rent stan­dard opti­cal com­par­i­son or stere­o­zoom microscopes.

Please also note that the cur­rent “Ballistic Fingerprints” data­base used for only crime guns, can eas­ily be run by trained police offi­cer and lab­o­ra­tory tech­ni­cians, up until the last step where a trained foren­sic firearm exam­iner is required to con­firm pos­si­ble matches. The trained police and lab tech­ni­cians can weed out nearly all non-matches, with­out the foren­sic firearm exam­iner need­ing to be involved.

It seems to me, that the tech­nol­ogy def­i­nitely needs more inde­pen­dent research. Research free of politi­cians with a bias for or against firearms, and free of input from com­pa­nies that stand to poten­tially make sig­nif­i­cant money.

Ultimately what we will prob­a­bly find with either or both tech­nolo­gies, is that the abil­ity to track where a firearm is used in a crime is inter­est­ing, but doesn’t iden­tify the PERSON respon­si­ble for the crime. We don’t lock “guilty” firearms in jail, we have to put the firearm into someone’s hand at the time of the crime. The cur­rent “Ballistic Fingerprints” sys­tem is gen­er­at­ing hun­dreds of hits across the coun­try, but the num­ber of court con­vic­tions seems to be VERY small. And shouldn’t the num­ber of crim­i­nals put behind bars and/or reduc­tion in crime rates be the mea­sure of suc­cess in police work?