First of all, Airlines are NOT responsible for broken/cut off locks or damage to bags due to forceful opening of checked in baggage, when done for security reasons. They do not offer any compensation in such situations.
Let me walk you through the baggage handling process at the airport. The airline’s job during check-in is to load your baggage on the conveyor belt at the check-in counter. They again collect it at the loading bay after they go through the screening. The airlines do not open your bags to check. Checking of baggage is the responsibility of the airport and customs authority. They are in possession of your bags before handing them back to the airline staff for loading. If either the airport security or customs authorities find anything suspicious during the X-ray scan, they have the authority to open your baggage. One might feel opening their baggage is violating one’s privacy, but it is their job to create a safe environment for travelers. Their area is under CCTV surveillance 24/7 so theft is almost impossible.
For international flights, it is a reverse process when you reach your destination. The baggage goes through customs clearance before handing over to the airline. It is a good practice to keep your checked bags unlocked. Airport security and customs have the authority to open it for suspicion. The airport and customs handle millions of bags day in and out. So, do not expect them to be gentle and courteous while handling your locked baggage.
Read more about – Luggage Interchange and Retrieval
If you travel within the United States, US CBP makes it very clear that they have the right to break open your non-TSA locked bags. It is also a provision in federal law.
Generally, it is not a good practice to lock your check-in baggage. If someone wants to tamper/open it, all it takes is a few seconds, whatever the purpose. Eventually, it is a damage caused to your baggage, which you have paid for, entirely your loss.
Personally, I never put a lock on my check-in bags, and I have never lost anything so far. On the contrary, the bags with locks grab attention and suspicion, leading to possible breaking/tampering.
Always remember that, majority theft from check-in baggage is reported from baggage that carries a lock.
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