Airport Screeners Still Aren't Any Good

They may be great at keeping you from taking your bottle of water onto the plane, but when it comes to catching actual bombs and guns they're not very good:

Screeners at Newark Liberty International Airport, one of the starting points for the Sept. 11 hijackers, failed 20 of 22 security tests conducted by undercover U.S. agents last week, missing concealed bombs and guns at checkpoints throughout the major air hub's three terminals, according to federal security officials.

[...]

One of the security officials familiar with last week's tests said Newark screeners missed fake explosive devices hidden under bottles of water in carry-on luggage, taped beneath an agent's clothing and concealed under a leg bandage another tester wore.

The official said screeners also failed to use handheld metal-detector wands when required, missed an explosive device during a pat-down and failed to properly hand-check suspicious carry-on bags. Supervisors also were cited for failing to properly monitor checkpoint screeners, the official said. "We just totally missed everything," the official said.

As I've written before, this is actually a very hard problem to solve:

Airport screeners have a difficult job, primarily because the human brain isn't naturally adapted to the task. We're wired for visual pattern matching, and are great at picking out something we know to look for -- for example, a lion in a sea of tall grass.

But we're much less adept at detecting random exceptions in uniform data. Faced with an endless stream of identical objects, the brain quickly concludes that everything is identical and there's no point in paying attention. By the time the exception comes around, the brain simply doesn't notice it. This psychological phenomenon isn't just a problem in airport screening: It's been identified in inspections of all kinds, and is why casinos move their dealers around so often. The tasks are simply mind-numbing.

To make matters worse, the smuggler can try to exploit the system. He can position the weapons in his baggage just so. He can try to disguise them by adding other metal items to distract the screeners. He can disassemble bomb parts so they look nothing like bombs. Against a bored screener, he has the upper hand.

But perversely, even a mediocre success rate here is probably good enough:

Remember the point of passenger screening. We're not trying to catch the clever, organized, well-funded terrorists. We're trying to catch the amateurs and the incompetent. We're trying to catch the unstable. We're trying to catch the copycats. These are all legitimate threats, and we're smart to defend against them. Against the professionals, we're just trying to add enough uncertainty into the system that they'll choose other targets instead.

[...]

What that means is that a basic cursory screening is good enough. If I were investing in security, I would fund significant research into computer-assisted screening equipment for both checked and carry-on bags, but wouldn't spend a lot of money on invasive screening procedures and secondary screening. I would much rather have well-trained security personnel wandering around the airport, both in and out of uniform, looking for suspicious actions.

Remember this truism: We can't keep weapons out of prisons. We can't possibly keep them out of airports.

Posted on October 31, 2006 at 12:52 PM • 47 Comments

Comments

PrisonGuardsWe'reNotOctober 31, 2006 2:03 PM

How silly. As if the incentive(s) for you, me, and 99.9% of the U.S. population, for (1) keeping weapons out of prisons, and (2) keeping weapons out of airports, were the same! Ask anyone you know, or ask any stranger:

1.) During the past 10 years, in which forum have you spent more time, airports or prisons?
2.) Do your family members spend more hours per year flying on commercial airliners, or as an inmate or guest or employee in a prison?
3.) During the next 5 years, in which place do you think you'll spend more time, airports or prisons?

It's not that we CAN'T keep weapons out of prisons. It's that we don't CARE to spend the resources it would take to keep weapons out of prisons.

A weapon gets into a prison. So what? It won't hurt me nor a family member, nor a friend.

A weapon gets on to a commercial airliner. Uh-oh. I or a family member or friend of mine might be on board.

Even if there are over one million people in prisons in the U.S., do you really think the other 299 million are as interested in spending our tax dollars to keep prisons "safe" from weapons, as we are in keeping our air travel "safe" from weapons?

RCOctober 31, 2006 2:07 PM

This comic strip mentions Schneier and Rivest:
http://xkcd.com/
Amusing.

On airport screening, probably a fairly non-intrusive screening would be effective enough, combined with other security measures.

FreedomOctober 31, 2006 2:30 PM

@PrisonGuardsWe'reNot

You seem to have missed the point. The security regime in a prison is far more draconian than would ever be allowed in a public place. The people who run prisons do try to stop weapons and drugs from being acquired yet there is almost always a way to get past the system. If you cannot keep weapons out of an environment like a prison, where guards have the right to lock you up and search you or your cell whenever they feel like it then how do you propose to keep weapons out of public places?

"It's that we don't CARE to spend the resources it would take to keep weapons out of prisons"

No normal prison will ever get the kind of resources required to eliminate weapons' it would cost too much. Yet somehow, we can afford to patrol public places across the whole of the country?

Bruce's point is that we should not kid ourselves that we will ever have perfect airport security and we should choose how best to use our finite resources for security.

Oh by the way, what was all that stuff about "A weapon gets into a prison. So what? ..." Perhaps you sincerely believe that everybody who goes to jail deserves to be there. I'd suggest that there are such things as miscarriages of justice and bad laws.

jayhOctober 31, 2006 2:32 PM

"The bad news is that their response is to start an investigation to find out who leaked the test results."

Typical. A while back some kid captured a video of a school teacher totally losing his temper at a student and behaving like a total ass.

The school responded by looking at ways to prevent video taping in school

derfOctober 31, 2006 2:36 PM

The complete and total incompetence of the TSA shows they may as well not even be there and there would still be the exact same security. Yet despite this lack of security, there have been exactly zero successful attacks against airplanes since 9/11.

As an American taxpayer, I demand my money back. Surely some enterprising lawyer out there could make a bundle on this as a class action suit.

X the UnknownOctober 31, 2006 2:43 PM

"Oh by the way, what was all that stuff about "A weapon gets into a prison. So what? ..." Perhaps you sincerely believe that everybody who goes to jail deserves to be there. I'd suggest that there are such things as miscarriages of justice and bad laws."

Not to mention the (presumably innocent) prison guards and workers, who are likely targets of weapons in the hands of prisoners. In fact, these people have very strong vested interests in seeing weapons kept out, and mostly have the powers and priviledges necessary to enforce their interests. The fact that they cannot succeed is just all the more telling.

AnonymousOctober 31, 2006 2:52 PM

@Freedom

"Bruce's point is that we should not kid ourselves that we will ever have perfect airport security and we should choose how best to use our finite resources for security."

I agree that that is Bruce's point, and I agree with that point. What is silly is the idea that the statement of, if I may paraphrase, "[If] We can't keep weapons out of prisons[,] We can't possibly keep them out of airports" is a truism. It isn't.

Bruce makes a good point, but he weakens it dramatically by claiming that a statement that's obviously not true, is true.

Runaway SteveOctober 31, 2006 2:57 PM

It's also kind of hard to make people actually STAY in prison if they are sufficiently armed (say, with machine guns and explosives).

GlobetrotterOctober 31, 2006 3:01 PM

The other day I was told at check-in that the bottle of wine I was carrying would not be allowed airside. I did not want to throw it away, so I took it to security anyway. The man in front of me was explicitly asked if he had any liquids with him. I was not asked. The screener simply looked at the bottle, put it in the tray with my laptop and X-rayed it. I picked up the wine and took it on board.

AnonymousOctober 31, 2006 3:11 PM

@X the Unknown and Freedom

"Oh by the way, what was all that stuff about "A weapon gets into a prison. So what? ..." Perhaps you sincerely believe that everybody who goes to jail deserves to be there. I'd suggest that there are such things as miscarriages of justice and bad laws."

No, I don't believe that. Whether any given person deserves to be in prison is irrelevant to my point.

"Not to mention the (presumably innocent) prison guards and workers, who are likely targets of weapons in the hands of prisoners. In fact, these people have very strong vested interests in seeing weapons kept out, and mostly have the powers and priviledges necessary to enforce their interests. The fact that they cannot succeed is just all the more telling."

You've amplified my point. The fact that the guards have the incentive, the power, and the privileges necessary to enforce their interests, yet they cannot succeed is in fact quite telling. It tells us there's at least one necessary element missing, for success. That element is resources. Ask any prison guard if he thinks doubling the number of guards where he works would not make his job safer, easier, or better in whatever way he defines as better. So why don't we do just that? Just double the number of guards? Or implement any of dozens of other suggestions that have a high degree of probability of success? Because people do not want to PAY for it. Where do you think the funding for those new resources comes from? If John Q. Taxpayer has a choice to fund activity A, which he believes he'll benefit from, or activity B, which he believes will not benefit him, which do you think he will do?

Since we (all of the U.S. taxpayers) have not succeeded in allocating enough resources (funds) to keep weapons out of prisons, is no reason to conclude that we cannot be radically more effective at keeping weapons out of airports, and off of commercial airliners. We can be, and for one reason: incentive.

Geoff LaneOctober 31, 2006 3:22 PM

"Remember the point of passenger screening. We're not trying to catch the clever, organized, well-funded terrorists. We're trying to catch the amateurs and the incompetent. We're trying to catch the unstable. We're trying to catch the copycats."

So, exactly how many "amateurs and incompetent" idiots have been caught?
Smuggling must be at an all time low, but nobody is boasting about the successes which suggests that there are none.

Andre LePlumeOctober 31, 2006 3:58 PM

Even if we considered the life of every prisoner and prison worker to be worthless, a reason to be diligent about not allowing weapons IN to prisons, is that they can be used to assist the prisoners in getting OUT. To the extent that the incarcerate population is, indeed, a "menace to society", this makes sense.

ThomasOctober 31, 2006 4:36 PM

@Bruce,
"""Remember this truism: We can't keep weapons out of prisons. We can't possibly keep them out of airports."""

Despite the TSA-induced waiting lines prisoners have much more time than airline passengers to fashion weapons.

They also have more privacy.

Richard BraakmanOctober 31, 2006 5:03 PM

@Anonymous: Do John Q. Taxpayer's interests really matter in this decision? I doubt Mr. Taxpayer was all that interested in spending billions on invading Iraq, but that happened anyway. Compare it to, say, Mr. Taxpayer's interest in strengthening levees against hurricane damage.

Aaron LuchkoOctober 31, 2006 5:23 PM

One thing we are good at however is games. For screeners I think one solution could be to make the job interesting by having very regular rewards and punishment based on catching "bad guys".

Basically create a group of people whos sole job is to try and sneak bad things (drugs, bombs, etc) past screeners. Absolutely anything goes for ways of trying to smuggle things on board and tests occur at a very high frequency so a screener expects to get at least 1 visit per day (shouldn't be too expensive compared to other measures, a single agent could visit a lot of checkpoints). Moreover an agent gets a $50 reward for catching someone and a $50 fine for missing someone.

Of course the real solution is good investigators but if they want good screeners this program should result in a much more clever and attentive group of screeners.

passing_thurOctober 31, 2006 6:00 PM

oh yeah sure lets search blond girls,families and some old people ? I spent the better part of friday at the Gainesville,Fl. airport waiting for my wife and had a front row veiw of the TSA checking people. I stopped counting after it got to 7-1(female- male) of the persons they pulled outta line, they even pulled more families w/kids than single males.

So just what good is this kind of screening? Yeah that little old lady of about 80yrs is a threat, lets dump out the contents of her bag to do a wipedown.

Many of the screeners seemed to overweight bullies on some power trip.


Halle BurtonOctober 31, 2006 6:21 PM

Since 2001 I have used my New Mexico Passport exclusively as my ID and haven't been stopped once. Maybe they all think that the 49th state is a foreign country.

UroxOctober 31, 2006 6:48 PM

Seattle's security checkpoints are solid. How do I know? Because they found a tiny, tiny vial of liquid in my baggage that I didn't even know was there.

I had all my known liquids in the regular 7x8 bag and nothing else known to me. They ran my luggage through the scanner and said something was in it. They unload and search my bag, can't find anything, and repack it and resend it through.

They still see something. They unload my bag , carefully go through it again, pushing down on everything, take apart the bag as far as it will go (undoing every snap and zipper and attachment), run the empty bag through, and run the contents through in a bin.

They now see something in the bin.

They then went through every thing in minute detail, turning out pockets even for something that might be stashed. Turns out, there was a small vial of essential oil in some silk flower petals I was bringing home with me. It was tiny (1cm by 3cm) and completely hidden by the petals, but Seattle's TSA still found it.

Still, this level of scrutiny is ridiculous considering what anyone could hide in a gel bra.

nksinghOctober 31, 2006 7:01 PM

I had the same experience in Seattle as well. They found a small bottle of eyedrops that I lost in my baggage.

Filias CupioOctober 31, 2006 7:13 PM

Expanding on Aaron Luchko's comment:

I suspect once a day isn't enough. Better to have a computer system where every so often (several times an hour?) it presents an image of a "bad" piece of luggage in place of the actual luggage. For each image the scanning person hits an "accept" or "reject" button. When they hit "reject" on a fake bad image, they get an immediate reward (and immediate penalty for hitting "accept".) When they hit "reject" on a real piece of luggage, it gets searched.

You'd need a very large number (thousands?) of "bad" luggage images, to prevent the workers flagging fake bad images by memory, and you'd need to prevent the image-viewer from seeing the bags going onto the machine, or they can pick them up by mismatch between the bag and the image. With modern technology, you'd probably have all the machines piping images to a separate room.

You might give the scanner worker three options instead: clean, suspicious and very suspicious. If a real bag is flagged "very suspicious", roving security guards are silently alerted to converge on the gate in question.

It would also make some sense to have the gate security staff join the penetration team sometimes. There is a risk in that some of the security staff could be terrorist sleepers, to whom you are providing valuable training.

AnonymousOctober 31, 2006 7:45 PM

From the article: "We can do better, and training is the path to improved performance," said Mark Hatfield Jr.

No, Mark, it's not. They already had training and this is the result, wholesale failure.

These were not tricky tests. They were gimmes.

From the results, it is clear most weapons would make it through inspection.

Humans are not equipped to work eight hour shifts at inspecting, inspecting, inspecting, inspecting, inspecting. They quickly -- in minutes, not hours -- get brain-dead. It's not their fault. The work is dull and we're not good at dull.

Full-time inspection is worse than sentry duty, because sentries at least get to look at the scenery. Even so, sentries quickly go brain-dead from mindless routine. (I learned how to get past the main gate guard unseen at the USMC base at Nebo.)

At the same time, hunters will spent long days on the hunt, because hunting is involving, it's challenging, it draws on all our knowledge and experience. It keens the senses and makes the brain work hard.

Unless we are going to use strategies and tactics that make good use of what humans are good at, there really is no point trying. The colossal fortune we're spending pretending to secure air travel is going to waste -- what isn't lining some opportunists' pockets.

RoyOctober 31, 2006 7:46 PM

From the article: "We can do better, and training is the path to improved performance," said Mark Hatfield Jr.

No, Mark, it's not. They already had training and this is the result, wholesale failure.

These were not tricky tests. They were gimmes.

From the results, it is clear most weapons would make it through inspection.

Humans are not equipped to work eight hour shifts at inspecting, inspecting, inspecting, inspecting, inspecting. They quickly -- in minutes, not hours -- get brain-dead. It's not their fault. The work is dull and we're not good at dull.

Full-time inspection is worse than sentry duty, because sentries at least get to look at the scenery. Even so, sentries quickly go brain-dead from mindless routine. (I learned how to get past the main gate guard unseen at the USMC base at Nebo.)

At the same time, hunters will spent long days on the hunt, because hunting is involving, it's challenging, it draws on all our knowledge and experience. It keens the senses and makes the brain work hard.

Unless we are going to use strategies and tactics that make good use of what humans are good at, there really is no point trying. The colossal fortune we're spending pretending to secure air travel is going to waste -- what isn't lining some opportunists' pockets.

Farquin N. CredibbleOctober 31, 2006 10:58 PM

"Remember the point of passenger screening. We're not trying to catch the clever, organized, well-funded terrorists. We're trying to catch the amateurs and the incompetent. We're trying to catch the unstable. We're trying to catch the copycats."

Damn right. If I get blown up on an airliner, I want to be sure it's a professional job.

Shoddy workmanship can be downright dangerous.

FoobOctober 31, 2006 11:13 PM

Why not just make sure there's a constant stream of 'mystery shoppers' going through every week? In other words, every security checkpoint should expect to catch at 5 weapons per week that are brought through by a staff of rotating individuals who's job it is to try to get past security.

The performance of each security checkpoint is measured by % that they catch the mystery shopper with points deducted for improper rule enforcement, bad attitude, etc.

That way, the screeners expect to find some creative way of hiding the weapons. And when the real crooks come through, the TSA will be well practiced to catch them.

bobNovember 1, 2006 6:59 AM

@Thomas: Everyone has the same amount of time; their entire life up to the point they started an event. Outside prison they have a lot more resources to disguise stuff with during that time. Inside prison they have fewer distractions.

@Aaron Luchko: I like that idea. It would also let them get their "suspect handling" processes more consistent and safe, since 90% of people they caught would be "good guys".

@passing_thur: there is no category of people you can eliminate from screening. Focusing primarily on 80yo grandmas is probably inappropriate, but she might be Ted Kaczynski's mother looking for revenge.

@Andre LePlume, others:The people in prisons with the weapons are the "worst cases", you dont want to reward them for their crimes by allowing them to extort things from the people who are in in prison for minor offenses. Plus the guy in prison for refusing to pay child support to his ex-wife because the tests prove its not his child shouldnt have to worry every minute about being stabbed to death for his political views.

@Geoff Lane: ALL of the ones caught were unprofessional.

ChicNovember 1, 2006 8:12 AM

If they are going to keep this system then they should at least offer bonuses for finding actual bombs and guns. A $2,000 or more reward for finding these dangerous items might go a long way in improving the test scores on these random trials.

PseudonymousNovember 1, 2006 10:11 AM

Actually, there is a way to keep weapons off airliners.

All passengers, without exception, will strip, undergo a full body-cavity search, and will be issued airline clothes (probably sweats and underwear). All personal possessions, including clothing, will be transported with the passengers in locked and sealed containers. (Extra credit if the airline can lose these, leaving passengers possessing nothing but the cheap clothing they're wearing in a strange city.)

This is, I believe, how prisons approach the problem of smuggled drugs and weapons. Given the more controlled circumstances, I'd expect this to work better in an airport.

Of course, some of you may not want to be subjected to strip search and body cavity search, or perhaps you don't want your young children subjected to it. However, I don't see that anything short of this is going to work.

Alternately, we could take the chance of weapons on aircraft, since precisely zero have been used in the last five years, and at least try to live up to being "the land of the free and the home of the brave."

gfujimoriNovember 1, 2006 10:13 AM

@Chic

I recognize that you are suggesting something to positively motivate the min-wage security workers. However, I think if you ponder the consequences of what that would do, you'd find some very ugly unintended results.

For that kind of money, with a little sleight-of-hand, a minimum wage worker could unethically increase their salary significantly. The false positives would be a nightmare as well: "I found liquid explosives - give me the money!!!" The supervisor would then look over and say, "Sorry, but it's definitely just water. Please let this passenger pass through."

PseudonymousNovember 1, 2006 10:16 AM

Oh, foo, I forgot something. The above (strip, body cavity search, carry nothing) will only work to stop passengers from bringing weapons aboard. It doesn't solve the problem of other people getting weapons to the passengers after they've been stripped and groped. I guess we need to close down all amenities in the secured areas, and do the same for everybody who works in the secured area or on the aircraft themselves.

X the UnknownNovember 1, 2006 12:06 PM

@Pseudonymous

Of course, for the maintenance workers this is a real problem - many of the tools of their trade can be directly used as weapons. No more mechanics allowed anywhere near airplanes, so we can't do repairs and maintenance. Airliners become disposable - great for the economy!

X the UnknownNovember 1, 2006 12:07 PM

@Pseudonymous

Of course, for the maintenance workers this is a real problem - many of the tools of their trade can be directly used as weapons. No more mechanics allowed anywhere near airplanes, so we can't do repairs and maintenance. Airliners become disposable - great for the economy!

MNovember 1, 2006 12:27 PM

.

.

.

There is an easier way to improve airline security:

1) Give up on this ban on liquids. Anyone who really wants to will make a belt-buckle out of elemental sodium and flush it. (Na + H20 = NaOH (drano) + H2 + heat. Boom.) Or they will treat their cotton cloths to make guncotton (boom). Or they'll sew explosives into the lining of their suit. Or any one of a million other things. Do you really want to ban metals and clothes?

Because anything less is a pointless inconvenience. (Not to mention a health hazard. Changing dirty diapers + lack of hand cleanser = people getting very sick! Similarly, breastfeeding + lack of replacement fluids = medical intervention for extreme dehydration.)


2) Give up on requiring identification. College kids can get fake IDs to buy booze. Can minimum-wage drones who've chosen to stand in front of a made-by-the-lowest-bidder X-ray machine for a living really tell the difference between real and fake IDs? Sure, there may be severe penalties for using a fake ID. But what do they matter to a suicide bomber?

3) Charge every passenger $10 more per ticket. Let non-passengers through, but charge them $10 too.

4) Half the passengers (semi-randomly selected) get PINK GUNS. A solid gun-shaped piece of metal dyed pink. Really obviously not a threat. Any passenger can refuse to participate. Any non-selected passenger can choose to participate.

5) If you can get your PINK GUN past security, you get $20.

6) At the end of the shift, whatever money has not been paid out gets divided up amongst the security screeners.

7) As security screeners get better, the $10 per ticket becomes $5 per ticket. Then perhaps $2 per ticket. Payout to winning passengers remains unchanged.


Look, you keep a human in a sterile germ-free environment, and the first cold virus that comes along kills them. But they live on a farm, shoveling manure every day, and they've got an immune system like a junkyard dog.

So lets strengthen our airport security the same way. A positive result shouldn't be a once-in-a-lifetime event. IT SHOULD BE EVERY OTHER PASSENGER!


.M.


AnonymousNovember 1, 2006 12:38 PM

@M

If I paint my 9mm Browning Hi-Power pink, can I bring that instead?

On second thought, maybe I'll paint a cheaper gun pink. I hate to ruin a good blued finish.

bobNovember 1, 2006 9:25 PM

"If I paint my 9mm Browning Hi-Power pink, can I bring that instead?"

Since when is a 9mm "Hi-Power"?

AGNovember 2, 2006 12:22 AM

Enact a policy to cut the scrotum off and duct-tape it into the mouth of anyone who smuggles weapons into jails or airports and the trend will end. Quickly.

Also, construct mass transit systems with cloth-covered pigskin leather as swine-shrapnel is an effective deterrent to Islamic terrorists.

Effective deterrents don't need to cost very much at all.

CJNovember 2, 2006 3:12 AM

Saw a related story this morning - http://www.int.iol.co.za/index.php?...

The scary part is this paragraph:
"...was charged with three offences, including preparing to commit or help others commit an act of terrorism, and possessing items useful to terrorists."

If we're going to start charging people for possessing items useful to terrorists - which, considering the hand luggage bans, could include knitting needles and tweezers - we might as well just give up on society now.

ThatguyNovember 2, 2006 3:54 AM

A "Hi-Power" is the model name of the gun.

I feel playing games with security will just cause mass delays. Jumpy workers will get loads of false positives. Might as well check everyone right? That is what will happen.

Low cost, less waiting time, solution: everyone that wants to carry a gun can. If you stand up with anything trying to hijack the plane, you are easily outnumbered. So why try. Cost the government no money, is voluntary, and security will not have to be so tight.

supersaurusNovember 2, 2006 6:07 AM

if I was going to lie awake at night worrying, I'd worry about the possibilities among people who are behind the security screen every day, e.g. maintenance, food service, cleaning, gate checkin, etc. locking the cockpit door has drastically reduced the likelihood of using the plane as a guided missile, so you are left with blowing it up. if you are going to blow it up wouldn't you rather it happen while you are safely sitting on the ground? sure, there are better and worse places to blow up a plane in the air, but again wouldn't you rather do it by radio or some kind of hookup to an in-flight gps than in person?

of course there is still the possibility of a pilot doing it, but you won't catch that by passenger screening.

MeNovember 13, 2006 4:32 PM

@AG - and from where will you get the scrotums to tape to the face of female smugglers? You act as if only men smuggle?

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