COLUMN: Ballistic fingerprints faulty

Published: Thursday, October 24, 2002


Terror inspires faith even in the most flawed of plans.

With the yet-to-be-named sniper lurking around our nation's capital, riddling innocent bystanders with bullets, anxiety is aroused and solutions are demanded. In times of crisis, fear and paranoia are louder than reason.

Every human has a unique set of fingerprints, one that rarely changes throughout the normal lifespan. Fingerprints have remained an essential key in criminal investigations. In cases like the sniper, where very little evidence is left behind, cries for ballistic fingerprinting in lieu of other evidence are being heard.

However, ballistic fingerprinting may not be the superlative alternative. Current drafts of fingerprinting programs call for the firing and kept shell record of each gun before it is sold. Guns leave unique impressions on each half of the cartridge post-combustion. Theoretically, forensic evaluations of the empty shell and the recovered bullet can be accurately traced to any gun that has been fingerprinted.

Keeping record of the cartridge scaring means noting how the bullet responds to the microscopic idiosyncrasies of each barrel and firing pin. Thus, ideally, two guns will never produce identical markings on a cartridge. From bullets or shells, crimes can be traced to a specific gun and its owner. Though appearing to be a panacea for murder, implementing a ballistic fingerprinting program would be headlong; several confounding variables have yet to be accounted for.

If all bullets could be traced with a relative degree of accuracy, the largest hurdle that proponents of fingerprinting must clear is persuading current firearms owners to hand over or fingerprint their firearms. To eliminate resistance, a reward could be offered. For each gun brought in citizens would receive their choice of a Sponge Bob Square Pants plush toy or some fruit. People, especially criminals who plan on shooting someone, respond well to healthy snacks.

More than 100,000 firearms were sold in the state of Georgia alone in 1998, meaning that there are millions of extant, unfingerprinted firearms in the United States. This is a problem that cannot be ignored. For ballistic fingerprinting to prove effective all firearms in the United States. must be accounted for. This, however, is impractical.

Even without manipulation, guns naturally change from use. After thousands of rounds have been fired from a gun, the dynamics of the gun are altered. Any gun, no matter how skillfully constructed, will never fire exactly the same every time. Thus, the first bullet fired from the gun and 5,000th may vary so drastically that fingerprinting is rendered impossible.

Opponents of the ballistic fingerprinting program are trying to shoot down the idea like a pheasant. Not only do they claim that fingerprinting is inaccurate, but also that the conditions affecting the bullet and shell can be manipulated for as little as $2.

With a fingernail file and a steel brush, the physics of any gun can be completely altered. Filling the firing pin will change the mark left on the shell butt, scraping the inside of the barrel with a brush will change the pattern of behavior that the bullet experiences when propelled down the barrel. Furthermore, steel rod brushes are used daily to clean gunpowder buildup. Thus, the unique characteristics of each barrel that initially made forensic discrimination possible disappear over time.

The most incriminating evidence against ballistic fingerprinting is yet to come. The jury is still out as to whether two bullets fired from different guns could be falsely identified as coming from the same gun. If we are to accept ballistic fingerprinting, we must first be assured that two guns could never produce identical, or, more importantly, similar markings on a cartridge.

A 2001 investigation in California indicated that ballistic fingerprinting is not an infallible measure, rather, a waste of time and taxpayer money. The study showed an error of 38 percent existed in matching bullets and guns if cartridges came from the same manufacturer. The error skyrocketed to 60 percent when the bullets came from different manufacturers. If a study of only 790 pistols had a 60 percent degree of error, how can supporters of ballistic fingerprinting deny the inherent flaws in the program? Hypothetically, if 1 million same-caliber guns were fingerprinted, a ballistic appraisal of shell or bullet could falsely pinpoint 600,000 different guns thus slyly, scientifically, and indirectly, incriminating an unacceptable number of innocent people.

In the United States, most crimes are committed with stolen or illegally acquired guns. Even though it's unlikely, ballistic fingerprinting may lead police investigating a crime back to the original owner of a gun even if the gun was stolen. If arrested, however, the owner will be presumed guilty. The ballistic fingerprinting program protects nobody while adversely increasing the risk that innocent gun owners will fall prey to scientific false positives.

With the sniper just having felled his 13th victim, cries for change in gun control are ubiquitous. Regardless of the flaws of the ballistic fingerprinting proposal, the "we have to start somewhere" attitude is, nevertheless, bound to be heard. But is fingerprinting guns sold from this date forth enough? Is a program with only 40 percent accuracy a violation of human rights if it is guaranteed to incriminate innocent people? Is the expenditure of millions of dollars really practical if a gun can be altered for less than the cost of a hot dog?

Like all firearm amendments, fingerprinting arrived too late on the crime scene.



You can contact Eric Howerton at erichow@unm.edu.