A better way to track a bomber

The blast site on Boylston Street between Dartmouth and Exeter streets near the Boston Marathon finish line.
(Robert F. Bukaty / Associated Press)

The mayhem in Boston the week of April 15 was a reminder of how an American city can be paralyzed by a homemade bomb. The same kinds of improvised explosive devices that menaced U.S. troops in Iraq and Afghanistan can easily be deployed by freelance terrorists or madmen trying to send a message, incite panic or just create a media spectacle.

The Tsarnaev brothers were identified because of surveillance videotape, but the FBI might have been able to do it faster if tiny plastic markers had been part of the small-arms propellant packed into the pressure-cooker bombs. These little chips, called “taggants,” have been around for close to 40 years, and their crime-solving capability is impressive. But they’re not used today because of one formidable opponent: the National Rifle Assn.

The idea behind taggants is both benign and ingenious, and it can be credited to a chemistry professor and former 3M employee named Richard Livesay, who had been angered over the 1970 leftist bombing at the University of Wisconsin that killed a graduate student. Explosions always create residue, and Livesay figured out that gunpowder could be seeded with bits of melamine plastic, which cannot be destroyed or melted. Each particle is about a tenth of a millimeter across and contains a layering of eight to 10 colors. They look like pepper flakes, and the specific color signature can be read with an infrared scanner, telling an investigator where that batch of explosive was produced and perhaps even the retail store where it was purchased.


FULL COVERAGE: Boston Marathon attack

After the Oklahoma City bombing revived fears of domestic terrorists in 1995, the Clinton administration asked the Treasury Department to study how taggants might be used as a traceable element in dynamite and gunpowder. But the NRA complained that the program could result in a registry of gun owners (the same argument that sank the recent attempt at a universal background check for firearms purchases).

Jim Pasco, a former assistant director of the Bureau of Alcohol, Tobacco, Firearms and Explosives, said the NRA “objected to record-keeping.” Manufacturers would have to keep logs of when and where different batches of explosives were distributed to retail outlets, which are already required to maintain records of purchases of explosives. The trail this generated would be broad — many retailers and many purchasers — but the process still came too close to the gun lobby’s discomfort with government surveillance.

That the proposal came from the ATF also didn’t help matters, according to William Vizzard, an emeritus professor of criminal justice at Cal State Sacramento and a former ATF special agent. The NRA’s distrust of the federal law enforcement agency was so great, he said, that “if we suggested having a picnic, they would have immediately denounced picnics as a communist plot.”

The NRA successfully pressured Congress to keep the ATF away from the issue, although it did participate in a National Academy of Sciences study of taggants in 1999. The outcome was a report that half-heartedly acknowledged that the plastic chips “could be of further assistance” in a forensic investigation and called for more research. The idea has lain dormant ever since.

Explosives manufacturers have no ideological opposition to taggants, but they do want to make sure the science is unassailable, the taggants don’t interfere with the use of their products and the cost isn’t prohibitive, said Christopher Ronay, the head of the Institute of Makers of Explosives, a lobbying and safety group. “Everyone would like to see a marker that’s durable and readable,” he said. As for NRA opposition, he said: “Frankly I don’t know why that would bother anyone — tracing a product back to its manufacturer.” When we asked the NRA last week if it stood by its decades of opposition to taggants, it declined to make a comment.


There is no doubt that requiring taggants would result in a marginally higher shelf price for gunpowder and dynamite; the ATF estimated the cost at 2 cents per pound of explosives in the mid-1970s, and that ratio has not changed. Although this isn’t an apples-to-apples comparison, it’s worth noting that economists have said closing down Boston for a day cost about $333 million; a few extra pennies are a bargain by comparison.

The NRA also suggested that taggants would be useless distractions to an investigation — “like finding a needle in a haystack” was the phrase a gun lobbyist used — but there is a case on the books that proves the opposite.

Federal agents were experimenting with taggants in 1979. They inserted them into explosives sold from a West Virginia plant. Later that year a steelworker in Baltimore named Nathan Allen was killed by a crude dynamite bomb placed under the seat of his truck. Taggants were found at the scene, and federal agents were able to narrow down a list of possible retailers, who then helped them figure out purchasers of the particular batch of explosives used. The list included Allen’s uncle, who suspected that Allen was having an affair with his wife. The uncle was convicted, and a federal judge later noted that “the use of taggants in explosives rests upon well-established scientific principles.”

After a bombing, police need every clue that a crime scene can yield. The 1993 World Trade Center bombing was quickly solved because of a clue in the wreckage: a serial number on a mangled axle that led the FBI to a Ryder truck dealership and then to the man who placed the bomb. Homicide detectives can trace the origin of a bullet by the unique groove markings of a gun barrel. Taggants would be a similar telltale signature. Just the fact of their presence would serve as a deterrent to kitchen-sink bombers.

Some courageous Republicans defied the NRA in 1996 to support a study on placing taggants in black powder. Congressman Henry Hyde (R-Ill.) was among them because, as he told a reporter, “I want my party to be the party of law and order, as it always has been, and not the party of the militias.”

With the Boston bombings fresh in everyone’s mind, Congress needs to stand up to NRA foolishness and resurrect this eminently good idea.

Tom Zoellner is an associate professor of English at Chapman University. Sam Kleiner is a student at Yale Law School.