Behavioral Assessment Profiling

On Dec. 14, 1999, Ahmed Ressam tried to enter the United States from Canada at Port Angeles, Wash. He had a suitcase bomb in the trunk of his car. A US customs agent, Diana Dean, questioned him at the border. He was fidgeting, sweaty, and jittery. He avoided eye contact. In Dean’s own words, he was acting “hinky.” Ressam’s car was eventually searched, and he was arrested.

It wasn’t any one thing that tipped Dean off; it was everything encompassed in the slang term “hinky.” But it worked. The reason there wasn’t a bombing at Los Angeles International Airport around Christmas 1999 was because a trained, knowledgeable security person was paying attention.

This is “behavioral assessment” profiling. It’s what customs agents do at borders all the time. It’s what the Israeli police do to protect their airport and airplanes. And it’s a new pilot program in the United States at Boston’s Logan Airport. Behavioral profiling is dangerous because it’s easy to abuse, but it’s also the best thing we can do to improve the security of our air passenger system.

Behavioral profiling is not the same as computerized passenger profiling. The latter has been in place for years. It’s a secret system, and it’s a mess. Sometimes airlines decided who would undergo secondary screening, and they would choose people based on ticket purchase, frequent-flyer status, and similarity to names on government watch lists. CAPPS-2 was to follow, evaluating people based on government and commercial databases and assigning a “risk” score. This system was scrapped after public outcry, but another profiling system called Secure Flight will debut next year. Again, details are secret.

The problem with computerized passenger profiling is that it simply doesn’t work. Terrorists don’t fit a profile and cannot be plucked out of crowds by computers. Terrorists are European, Asian, African, Hispanic, and Middle Eastern, male and female, young and old. Richard Reid, the shoe bomber, was British with a Jamaican father. Jose Padilla, arrested in Chicago in 2002 as a “dirty bomb” suspect, was a Hispanic-American. Timothy McVeigh was a white American. So was the Unabomber, who once taught mathematics at the University of California, Berkeley. The Chechens who blew up two Russian planes last August were female. Recent reports indicate that Al Qaeda is recruiting Europeans for further attacks on the United States.

Terrorists can buy plane tickets—either one way or round trip—with cash or credit cards. Mohamed Atta, the leader of the 9/11 plot, had a frequent-flyer gold card. They are a surprisingly diverse group of people, and any computer profiling system will just make it easier for those who don’t meet the profile.

Behavioral assessment profiling is different. It cuts through all of those superficial profiling characteristics and centers on the person. State police are trained as screeners in order to look for suspicious conduct such as furtiveness or undue anxiety. Already at Logan Airport, the program has caught 20 people who were either in the country illegally or had outstanding warrants of one kind or another.

Earlier this month the ACLU of Massachusetts filed a lawsuit challenging the constitutionality of behavioral assessment profiling. The lawsuit is unlikely to succeed; the principle of “implied consent” that has been used to uphold the legality of passenger and baggage screening will almost certainly be applied in this case as well.

But the ACLU has it wrong. Behavioral assessment profiling isn’t the problem. Abuse of behavioral profiling is the problem, and the ACLU has correctly identified where it can go wrong. If policemen fall back on naive profiling by race, ethnicity, age, gender—characteristics not relevant to security—they’re little better than a computer. Instead of “driving while black,” the police will face accusations of harassing people for the infraction of “flying while Arab.” Their actions will increase racial tensions and make them less likely to notice the real threats. And we’ll all be less safe as a result.

Behavioral assessment profiling isn’t a “silver bullet.” It needs to be part of a layered security system, one that includes passenger baggage screening, airport employee screening, and random security checks. It’s best implemented not by police but by specially trained federal officers. These officers could be deployed at airports, sports stadiums, political conventions—anywhere terrorism is a risk because the target is attractive. Done properly, this is the best thing to happen to air passenger security since reinforcing the cockpit door.

This article originally appeared in the Boston Globe.

Posted on November 24, 2004 at 9:33 AM12 Comments


Martin Johnson November 24, 2004 11:36 AM

I think its time for everyone to have a serious discussion concerning the concepts put forward in The Truth Machine by James Halperin (

Are programs in the works to create a better, faster lie detector? That seems to me the most fail-safe way to catch terrorists or anyone with criminal intent. Instead of a metal detector a passenger is simply asked a series of questions concerning his intent once boarding a plane, etc.

Arik November 24, 2004 12:02 PM

Just a note – Israeli airport security is done by a private security company contracted by the “Airfields and Ports Authority”, not the police.

Yes, they’re audited a lot.

— Arik

Fact-check November 24, 2004 12:06 PM

Hi Bruce.

The Ressam story changes every time it’s told — and more inaccurate each time it’s told.

Ressam was not carrying a “suitcase bomb” or any other kind of bomb. The term “suitcase bomb” is typically used to describe a one-kiloton Soviet-era portable nuclear bomb, or the portable US Special Atomic Demolition Munition (SADM).

Ressam was carrying commonly available fertilizer in the spare-tire compartment of his car. He also had with him a couple of jars of nitroglycerin-related chemicals to turn said fertilizer into an explosive.

If you have eggs, flour, sugar and baking powder in your grocery bag, do you have a cake? No, obviously not. The best that could be said was that he had some of the ingredients to make a bomb with him when he crossed the border, which is a small but important distinction.

Unfortunately, linguistic shorthand, lazy reporting, sensationalist newscasts, fear-mongering and the oft-repeated myth of the massive bomb that Ressam was carrying have seeped into the public consciousness and all but eradicated the facts of the case.

If people are repeatedly told something is true, they will eventually believe it to be true, even though the facts say otherwise.

Let’s move beyond fear and myth and back into the business of accuracy, facts and reality.

DaveC November 24, 2004 3:22 PM

Responding to “Fact-check:”

At least to me, “Suitcase bomb” does not imply a portable nuclear explosive (although I suppose it could in some contexts).

Nitrogylcerin related chemicals are notoriously sensitive and meet the usual definition of explosives. My recollection of video interviews with some of the customs officers involved in the search includes statements from the officers that they concluded that Ressam was quite anxious that the bomb making materials would explode during the search of the vehicle.

While “suitcase bomb” is not a precisely accurate description of Ressam’s cargo, functionally the cargo was the same thing.

Greg Black November 24, 2004 4:16 PM

Any chance of fixing the comments so that they don’t destroy the article? Somebody posted a long URL and now we have to scroll miles sideways to read impossibly long lines. And why are email addresses required to post comments, especially when they’re then made available for scraping by spammers?

Scot Mcphee November 24, 2004 11:01 PM

Suitcase bomb not a nuke? I always thought that’s what they were. So does Google; first five entries googling for “Suitcase Bomb”; – US & World – “Suitcase” Bomb
… “Suitcase” Bomb. Wednesday, January 29, 2003. BACKGROUND. What Is It? A
“suitcase” bomb is a very compact and portable nuclear weapon …,2933,76990,00.html – 31k – 24 Nov 2004 – Cached – Similar pages

Suitcase Nuke – Suitcase Bomb Information
Suitcase nuke,suitcase bomb,backpack bomb information and homeland security
preparedness guides. What to do before,during and after … – 15k – 23 Nov 2004 – Cached – Similar pages

The Destructive Effects of a Nuclear Suitcase Bomb
The Destructive Effects of a Nuclear Suitcase Bomb. by Roland Watson. The … open.
Does Bin Laden still own the fabled nuclear suitcase bomb? … – 25k – Cached – Similar pages

Nuclear Suitcase Bomb Feedback
Nuclear Suitcase Bomb Feedback. by Roland Watson. I got a fair bit of email
correspondence from LRC readers regarding my article on ... - 15k - Cached - Similar pages 

Are Suitcase Bombs Possible?
… described. A suitcase bomb with dimensions of 60 x 40 x 20 centimeters is
by any standard a very compact nuclear weapon. Information … – 12k – Cached – Similar pages

Nick Barron November 25, 2004 4:15 AM

A suitcase bomb is a bomb in a suitcase. The fact that journalists decide it’s a nice term for a man-portable nuclear device doesn’t make that the sole meaning of the term. The most commonly described US one for example is officially called the “W54 Special Atomic Demolition Munition”, and looks more like a flightcase than a suitcase.

On the subject of computerised screening, or any such “profiling”, the following may be of interest as a possible example of how such systems can actually reduce security compared to random screening:

Douglas Brebner November 26, 2004 12:52 PM

“He was fidgeting, sweaty, and jittery. He avoided eye contact.”

Sounds like a few aspies (autistics) I know.

T_Bushmaker November 26, 2004 2:40 PM

The article is about behavioral assessment profiling.
I pass thru security portals on a regular basis. I have noticed people watching the procedures, and closed-circuit cameras and lens movement. How many people are watching? Who are they watching?

Clive Robinson November 29, 2004 9:57 AM

Two things,

1, Lie detectors, they are usually very fragile, not very reliable and not suited to use in anyhting other than controled environments. In most cases they look for signs of stress in people (voice stress, breathing rate, skin resistance, eye movment, etc). You usually need to ask quite a few training questions, at the start and throughout the test. You also need a well trained analyst to interpret the results. Oh and with practice most people can beat a lie detector test (as can most psycopaths). It has been reported on several occasions that the Scientologists actually trained their own people to pass lie detector tests with their own home made lie detector.

2, A fertaliser bomb is usually made with,

40-40 Nitro Chalk fertaliser (around one
hundred weight or a bag).

Coal Dust or other carbon source say charcol
(around six pounds)

Deisl / Gas Oil (around a pint)

Oh and a cement mixer to mix it all up (It’s how they do road resurfacing and some open cast mining in South Africa amoungst other places).

However all of these substances are routienly found around a farm and some green/glass houses (for growing palm trees in cold climates)

The problem is that you cannot set Nitro-Chalk bombs off with a conventional detinator, you need an itermediate explosive with high energy output and very rapid burn rate to get over the entropy hump. It is quite a stable explosive from this point of view.

As for “nitroglycerin-related chemicals” this would be,

Concentrated Nitric acid
Concentrated Sulfuric acid

The Two acids will be found comonly in motor shops and the glycerin in a cake shop. You will also need some glass ware and quite a bit of ice and probably a frezzer as well.

However Nitroglycerin is not realy a suitable intermediate explosive for several reasons, not least that although very unstable (especially when making it) it can be quite dificult to set off reliably.

Alfred Nobel made his vast fortune from finding a way to tame “Blasting Oil” and make it both stable and reliable (which is the bit most people forget). But even so the mortality rate in his works was still very very high.

So the question is even if he did have all the chemicals (and I doubt that he did) would he have been able to make a useful bomb (I have my doubts).

All of the chemicals are very very easily available in most places (except for Northan Ireland) usually without question. Also the prefered explosive in the US used to be that you could get in gun shops in one pound tins again usually without question (I think at one point even Walmart sold stuff for self loaders). So, if he was dumb enough to carry all the chemicals then I doubt he would have been able to make the Nitro.

Oh and a story about portable nukes,

In the UK there used to be an establishment in Harwell Oxford that was supposed to do reasurch into such things. There was a story that kind of made it’s way through the armed forces that they had developed an “Nuclear hand grenade” that had an effective radius of some three hundred yards. The story teller would then say “but the trouble is your average squadie can only through thirty yards so they scraped it”.

RHJunior August 14, 2006 10:27 PM

and with the exception of only the Unabomber–who was a random loony, not even following the pattern of a terrorist— every one of the examples listed was Islamic, or had islamic ties. (They were following an evidence chain tying Mcveigh to an islamic cell before the Clinton government hushed it up.)

Call it a big forking hunch, but maybe you should start checking with the people who bow to MECCA.

gilly August 17, 2006 5:46 AM

Behavioral profiling is simply a characteristic human search and cataloging activity which we all perform on a daily basis, translated into a formal tool for societal security.

FYI, as a 7 year old Israeli and American caucasian girl, in 1967, flying to Israel, I was body searched each time by El Al security…El Al certainly did not reduce itself to racial profiling then or now…especially when there were incidents involving northern European terrorists in plain view-behavioral profiling is just common sense for all humans.

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