The recent sniper shootings around Washington, D.C. have prompted lawmakers and ordinary citizens alike to look for ways to help police solve similar cases. One idea that is getting a lot of attention is a national ballistics database, sometimes called ballistic fingerprinting.

What is ballistic fingerprinting?

When a gun is produced, the metal is formed and scraped away in ways that leave unique imperfections on the barrel. These imperfections leave marks on each bullet fired.

Police already use computer technology to compare bullets and determine whether they've been fired from the same gun. This technology has connected the Washington sniper shootings to one another.

Now, law enforcement officials, the federal Bureau of Alcohol, Tobacco and Firearms (ATF) and several members of Congress are calling for a law requiring gun makers to record this "fingerprint" in a computer system. Bullets or casings from a crime scene could then be traced to the gun they were fired from, and from there, through serial number records, to the owner. At least, that is the idea under ideal circumstances.

Support and criticism

Before the sniper attacks, the Bush administration was skeptical of the plan, saying the technology might not be reliable and could infringe on privacy. But on Oct. 16, White House spokesman Ari Fleischer said the president wants to look into creating a national ballistic registry.

"The president wants this issue explored. And to that end, the [ATF] has been meeting, and met yesterday afternoon with White House staff to start to discuss the various issues: The technical issues, there are feasibility issues, the pros and cons about how this could possibly... may be effective, whether it could work or whether it would not be able to work," he said.

One group that is strongly opposed to the idea is the National Rifle Association (NRA). The organization says there are flaws in the technology that would make the system at best highly imperfect, and at worst, could implicate an innocent gun owner in a crime.

Is the technology reliable?

Questions have emerged about the reliability of the technology. A Wall Street Journal editorial points out that unlike human fingerprints or DNA, gun "fingerprints" change over time as the gun is fired repeatedly.

However, Joe Vince, the former chief of the crime guns analysis branch of the ATF says that after repeatedly firing a gun, its "fingerprints" can still be compared. "We test-fired a gun 5,000 times, and the technology was able to match the first round with the last round," Vince told the New York Times.

That doesn't mean that a criminal couldn't purposefully change a gun's markings. Although the barrel of a gun is made of very hard steel, Dr. Ronald Brace, a spokesman for Doctors for Sensible Gun Laws, says criminals could foil investigators by filing the inside of the gun barrel or by simply changing barrels.

Privacy concerns

The NRA says it also opposes the database for privacy reasons. Ballistics fingerprinting, NRA officials say, "is national gun registration." Their concern is that if the government registers the guns of law-abiding citizens, it would have a list of guns to confiscate if it decided to. The group notes that criminals would probably not register their guns, casting wrongful suspicion on gun owners.

Former ATF agent William Vizzard, who favors a database, says the scope of the task is daunting. For such technology to be really useful, Vizzard says the "fingerprints" of all 200 to 250 million guns already in circulation would need to be entered into the database. But he says no one is really suggesting that.

"The mechanics of simply trying to track down those guns and get some sort of record on them is extremely difficult," he said during a NewsHour interview.

Costs and benefits

Also, the cost of initiating and maintaining such a database is unclear. In the two states that have experimented with ballistic databases, New York and Maryland, the systems cost around $5 million per year to get up and running.

But to former ATF officer Vince, the advantages outweigh the costs. He sees a ballistics database as the logical next step following the available technology, to improving the tools law enforcement has available to it.

"We have to start somewhere. We've put the equipment everywhere in the United States. Now we have to effectively use it as a law enforcement tool," he said during the NewsHour discussion.

Even if the database gains acceptance, it would be a long time before it is approved, never mind implemented.

By Emily Birr, Online NewsHour