At 2 p.m. on Tuesday last week, the Minneapolis-St. Paul International Airport went on lockdown when a bomb-sniffing dog sat down in front of a ratty pink bag on a carousel used by Continental Airlines.
The dog's handler sprang into action, immediately notifying her nearby supervisor. Under advisement from the Transportation Security Administration, the head of airport security's command staff called for the evacuation of half the baggage claim and ticketing areas in the Lindbergh Terminal and closed down a nearby road, causing a traffic jam.
The next step in airport protocol was to find the owner of the suspicious bag. Security contacted Continental to identify the passenger. That's when someone from the airline realized it was actually Continental's "last bag," a gaudy piece used to signal the end of the line. It was about 2:30 p.m., and every news outlet and Twitter user in town was reporting that the suspicious bag had come off an in-bound flight, which is what MSP had told reporters.
Even though security now knew the bag belonged to Continental, the high alert and lockdown continued for another hour. Patrick Hogan, Metropolitan Airport Commission spokesman, defends the decision.
"The dogs are reacting for a reason," says Hogan. "They're only trained to identify a certain chemical that can be used in an explosive. When they respond we are going to get everybody out of harm's way."
In this climate of hypersensitivity to national security, it's to be expected that airport officials would make the cautious call, says Bruce Schneier, international security guru and author of Schneier on Security.
"It doesn't matter what's right; people will do the thing that is most conducive to keeping their career," says Schneier. "Because being wrong, no matter how rare it is, is disastrous to your career."
Airport security brought in a second of their six canines to test its reaction to the bag. The second dog also hit on the luggage.
The Bloomington Police Department bomb squad X-rayed the bag and ultimately determined it was a false alarm—there was no bomb.
While it's reassuring there was never a real threat, the incident wasn't without cost to the airlines and passengers. Airlines at the Lindbergh Terminal likely lost a combined total of more than $1 million, estimates Bijan Vasigh, managing director at Aviation Consulting Group, LLC. Vasigh says there is often a ripple effect when flights are delayed, which would mean an even bigger financial blow. Hundreds of passengers also lost untold hours of productivity.
The false alarm was almost assuredly not the fault of the bomb-sniffing dog, says Doug R. Laird, former security director for Northwest Airlines and president of a private aviation consulting firm. "The dog knows what it's doing; the dog did what it's supposed to."
The most likely explanation is that the bag had been used in a past training exercise during which it came in contact with explosives, Laird says. "I can't think of any other scenario, I really can't." Bomb residue can stick to a piece of luggage for up to a year, he says, and bags are often accidentally mixed back into the shuffle at airports after use in canine training. Laird has seen this same mistake before.
But MSP's Hogan adamantly maintains that this is not the case. "This is not one that we have used in any kind of detection training in the past," he says. Hogan theorizes that the bag contained a common household chemical also used to make bombs, causing the dog to identify it as an explosive.
While it's possible for an everyday chemical to set off a bomb-sniffing dog, it's extremely unlikely in this case, says Patrick Beltz, chief canine instructor at Work Dogs International. Beltz says a homemade explosive, known as an HME, is one of at least 13 explosive devices every bomb-sniffing dog in the country is trained to detect, and they often contain household chemicals like hydrogen peroxide and acetone. "But I don't see how these things could be in that bag," Beltz says. "It's an airline bag, it's only used as a marker."
The airport has given the bag to the TSA, which will likely use it for future training exercises, says TSA spokeswoman Carrie Harmon. The TSA will assess Tuesday's incident, Harmon says, but it will keep the findings private.
No matter what caused the dog to hit on the bag, incidents like last Tuesday's are only going to become more common, says Dr. Richard Bloom, director of terrorism intelligence and security studies at Embry-Riddle Aeronautical University. National security scares like the failed underwear bomb on Christmas inevitably lead to a rash of false alarms in the weeks that follow.
"At least in the short- to midterm, if not the long term, the very psychological experience of going through that affects peoples' future behavior," Bloom says. "The tendency is to become more conservative and more rigid about implementation of your security procedures. That almost inevitably increases what I'll call our 'false-positive rate.'"