Originally Posted by
tesspug
Actually - you are allowed to lock luggage. The TSA just has the right to remove them for searches, if they decide your bag needs a physical search. Non-TSA locks are normally just cut off. The TSA has partnered with luggage & lock companies to make TSA approved locks that essentially have a master key for the TSA to use. This allows the TSA to have access, yet protects your luggage from non-TSA personnel.
Here's the TSA webpage explaining them:
http://www.tsa.gov/travelers/airtrav...ant/locks.shtm