I recently returned to the U.S. from a business trip. I claimed my bag at the baggage claim area. As this was an international flight, I was on the arrival side of customs. Still a secure area or maybe sterile area. I half opened my bag to put something in I no longer wanted to carry. A police officer informed me I wasn't supposed to open my bag as it was still a secure area. I thanked him and went through customs without being stopped. On the other side of the door my bag was taken by an airline employee and put on a conveyor to be re-loaded. That employee told me I could open my bag all day long there. So, what is wrong with opening my bag in the baggage claim area? It's not like I was able to carry something I shouldn't have onto the departing flight. I couldn't obtain something in the passageway between my arriving flight and baggage claim. Sure, I've read the story about someone opening their bag in baggage claim, pulling out a gun and shooting people but that could happen when you walk out the other side of customs. Seems to me the regulation may have been mis-interpreted. What does the regulation say? What is the regulation number?
It's probably a simple security considerations.
In the secure area, certain items (like a knife) are not allowed as carry on. At the baggage claim, you could potentially take a knife out of your bag and put it in your backpack.
The boundaries between secure and unsecure area in an airport are well defined. It's the security screening point on the way in and the guarded exit from the terminal and the customs exit door area to the arrival hall for international arrivals. All of these boundaries are staffed with people to guarding against illegal access.
Once you are out, the only way to get back in is to go through security (which theoretically would find your knife).
In most cases it will make little difference. There is no easy way to get back from baggage claim to the terminal and board a plane with the knife. You'd have to go reverse through immigration which is generally not possible. However the barrier that between you and the terminal is NOT a security screen.
I half opened my bag to put something in I no longer wanted to carry.
Just do that once you are out of the customs door. At this point you have entered the US and are no different than any passenger that has just arrived at the airport from outside (other than having a different bag drop). Once you are outside, you can repack and reshuffle as much as you want, because you are guaranteed to go through security again before being inside a terminal
When entering the US, you:
- Pass through immigration,
- Collect your bag,
- Pass through customs (blink and you'll miss it)
- and then exit into the outside (where your bag can be re-loaded for your domestic flight)
You seem to be talking about opening your bag between steps 3 and 4.
While I've probably done something similar, technically your are still in a secure area when you do this, so I can imagine that an official could take offense to doing what you did. (Likewise they would probably take offense if you started taking photos.)
As to why doing this might be an issue, consider that you want to avoid some import duty on an item that is in you checked luggage, (or even an illegal import) . One way to do that would be to pull it out of your bag prior to customs and then hide it on your body. Then pass through customs and only declare what is left in your luggage. Yes, this is probably a nonsensical way to smuggle things, but customs people are dealing with a range of people.
At the end of the day it is better (for them) to have an absolute rule that is easy to enforce, than to have to think about a myriad of different scenarios, (regardless about how nonsensical it is to you.)