According to icontainers.com, only 2-10% of all shipping containers are inspected.

What is the rationale for very thoroughly searching passengers and their belongings for drugs, when a simple opening of the bags could indicate that the passengers isn't carrying drugs in bulk? Given that the majority of shipping containers aren't controlled, this seems like a hugely disproportionate effort.

Edit: As pointed out in the comments, the rate of passenger searches is orders of magnitude lower. This source claims about 0.07% of passengers are searched:

Approximately 140 million passengers entered the United States on international flights during the two fiscal years 1997 and 1998. From these arriving international passengers, Customs inspectors selected about 102,000 passengers for some form of personal search.


  • 9
    AFAIK the instance of passenger searches for drugs is vastly lower than the instance of container searches for drugs. Maybe you are speaking of a particular problematic jurisdiction?
    – user6726
    Commented Jul 23, 2022 at 21:54

3 Answers 3


Passengers are not routinely screened for drugs

Normal passenger screening is to detect explosives and weapons, not drugs. That said, if you have two slabs of cocaine in your carry on, the x-ray operator will probably detect it.

Most drug mules carry the drugs internally which is extremely dangerous but, then, you’re a drug mule, you haven’t chosen a safe profession. Normal airport screening doesn’t detect this.

Drug mules are caught due to intelligence (i.e. they know this person is carrying drugs before they even leave home) or because the person acts suspiciously and is pulled out for interrogation.

The same applies to the linked article about containers. Most of those inspected are not random, they’re targeted, either due to pre-existing intelligence or because the container itself raises red flags. Random inspections are almost useless because it’s a needle in a haystack problem. The overwhelming majority of shipping containers are not used to import drugs - it’s simply not cost effective to do them.

  • 2
    @Rubus There's more than just containers. Tasbir Singh was caught trucking 2270lbs (~1030kg+) in marijuana, so someone lost $3.6m US in sales. Most drugs from Mexico are smuggled in cars or light trucks. Drugs from China are mostly sent in mail-order packages. It's all about risk management. It's harder to catch ~2000 mules than 1 container. So, more drugs go through mules to minimize loss.
    – phyrfox
    Commented Jul 24, 2022 at 14:46
  • 1
    The question is about customs inspection, not security inspection. The primary purpose of customs inspection is not in fact to detect explosives and weapons.
    – phoog
    Commented Jul 24, 2022 at 14:58
  • 5
    you haven’t chosen a safe profession — drug mules do not necessarily act out of their own free will.
    – gerrit
    Commented Jul 25, 2022 at 7:50
  • 1
    @gerrit it may not necessarily be the immediate choices that are in play here - it could be a series of choices stretching over a considerable time period. Also, its not intended as a serious commentary.
    – Dale M
    Commented Jul 25, 2022 at 8:44
  • 1
    However I have come across sniffer dogs at baggage reclaim on arrival. They probably are looking for drugs, and when they're on duty most bags get checked. I'm pretty certain once was at Denver, and also in Europe somewhere.
    – Chris H
    Commented Jul 25, 2022 at 9:18

Why are passengers inspected so thoroughly for drugs when most drugs enter through ports and the majority of shipping containers aren't controlled?

This question is a bit like asking "why are bar and restaurant patrons screened so thoroughly for age when the majority of underage drinking occurs outside of bars and restaurants?" That is, it's entirely possible that most drugs enter through cargo ports precisely because anti smuggling measures at airports are effective.

What is the rationale to very thoroughly search passengers and their belongings for drugs when a simple opening of the bags could indicate that the passengers isn't carrying drugs in bulk?

It's fairly straightforward to conceal things such that their presence is not revealed by "a simple opening of the bags."

Given that the majority of shipping containers aren't controlled this seems like a hugely disproportionate effort.

Whether this is true depends on the costs and benefits of each intervention. As noted in the first paragraph, the benefits include not only easily measured benefits such as the quantity or proportion of drugs seized in each context, but also on benefits that are difficult to measure, such as the deterrent effect of the screening. If air passenger screening were reduced, smugglers would notice this, and the quantity and proportion of drugs being smuggled by air passengers would increase.


Interesting claim in the source you cited, although it's really more of a blurb than an article. They even call it a "fun fact", which is far from an investigative report or something. Also, the source seems to be in the business of "helping" small businesses that are new to importing freight containers which makes me question their motives to be honest.

Allow me to inject into this thread some information about the technical and administrative features of shipping intermodal freight containers internationally.

There are two main cases:

  1. set up a sham business that pretends to be a legitimate importer, but actually puts contraband in the containers.

  2. sneak your contraband into the shipment of another legitimate company who has a container enroute to the US.

For case 1, setting up a sham business

In this case, the safeguards against money laundering are the most likely finder of your misdeeds. Highly unlikely to succeed. The "fun fact" in your cited article even acknowledges this in this part:

In fact, it’s easier to list why your container may be tagged for inspection than >why it wouldn’t. Here are a few:

If you’re a virgin importer, US Customs may inspect your first few shipments to >establish credibility .....

For case 2, sneaking your goods into some else's shipments

This is actually much more common, and so more interesting, at least to me.

Who has the opportunity to sneak some contraband into a container that is being shipped to the US from an unwitting company somewhere overseas? The company's shipping employees. The truck driver (or two, or three) who delivers the container to the point of debarkation. Someone following the truck driver who knows the container's destination, and tampers with the shipment at a rest stop. Every employee at the port while the container sits there waiting for its ship. Crew members on the ship -- maybe, depends on if the container is accessible, if it's buried at the bottom of a stack then crew members won't be able to help.

Ok your shipment has cleared customs, now you need to get it out of the container before your mule company gets wise. You going to pay off a port workers in the receiving country? A truck driver? How can you guarantee the driver on your payroll gets assigned the right container?

Assuming all your nefarious plans go perfectly, what stops this from happening?

  • Firstly, there is this:

In fact, it’s easier to list why your container may be tagged for inspection than >why it wouldn’t. Here are a few: .... If the weight of your container doesn’t correspond to the packing list

Typical freight scales on a crane or container handler round to the nearest 50lb (23kg), so if your shipment is >26lb(12kg) more than the paperwork, that container will be scrutinized. You're going to have to pay off a lot more truck drivers or port workers if you can only put 20lb of contraband in each container.

Also, there's this, which is worse: containers have tamper evident seals with unique serial numbers. Interlopers cannot open and re-close containers without leaving visual evidence. The seal serial numbers are on the paperwork. Here is an example that anyone can buy:

enter image description here

Here's a video about seals and how to apply them


And here's a video about trying to defeat a seal, which I think is debunked by the first video. Clamping a seal in a drill chuck will surely cause exactly the deformation the first video warned you to check for.


There are a few other "attacks" on container seals that I can assure you customs inspectors are well trained on detecting since even a fool like me has been trained on them. And I don't work in customs.

And one more thing: the containers themselves have features to prevent you from opening or taking off the doors in lieu of breaking a uniquely serialized tamper evident seal.

  • They have "customs catches"

The serialized seal is typically on the right side of the door. There is a piece of steel overlapping the left side that prevents the left side from opening first. So you cannot open the left side even though there is no seal on the left side. This piece of steel is either welded or attached with carriage bolts that can't be opened from the outside. See the top right caption of this diagram: parts of a freight container door

What prevents you from disconnecting the vertical securement bars from the door panels? If you look at the hinge brackets, you will see that each one is held on with either 4 or 6 bolts. And of those 4 or 6, one of them will either be tack-welded to the door panel, or else will be a carriage bolt that cannot be removed from the outside. After doing this operation and replacing it, there will be obvious visual unmistakable evidence to any customs inspector that the container has been tampered with. Paint fades. Your new paint will stand out like a sore thumb. Unfortunately I can't find a good picture of this using Google images. Find a container and see for yourself though.

What prevents you from tapping the hinge pins out of the hinges and removing both doors as a single big piece? Those hinge pins are either tack-welded or otherwise secured. The same concerns as the last paragraph apply. Your paint touch up after inserting the contraband will be painfully obvious. Can't find a picture of this either, so go find a container.

And consider this: a used freight container is pretty cheap. Nobody touches up the paint on them because it's not worthwhile. By the time the paint needs retouching, the container is only worth a couple of thousand US dollars. Repaint costs much more. So evidence of paint retouching on a freight container is a sure ticket to a thorough customs inspection.

  • "if it's buried at the bottom of a stack then crew members won't be able to help": but a conspirator with influence over the loading of the ship could help ensure that the container is accessible, or perhaps the container could be selected after the ship is loaded.
    – phoog
    Commented Jul 25, 2022 at 10:28
  • While there are a number of good points, the difficulties are... not that difficult, apparently. Commented Jul 25, 2022 at 19:17
  • @Italian Philosophers 4 Monica very interesting article, I wish they included more technical details about how the containers anti-tamper features were defeated! Commented Aug 3, 2022 at 2:46

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .