There will not be a law in your state that specifically covers your situation. There is a code that may cover the situation that may have been adopted by your state, and that is called the UCC. The UCC covers many commercial transactions and describes the duties of commercial contract
parties in certain situations.
Moreover, this will be covered by contract law principles as well. What does the contract say is your company's duty after you receive sealed cartons. Is it your duty under the contract to open each package to make sure that it contains shoes? If not, then you have not breached the contract. The buyer does not have a cause of action
against you in that situation, it has a claim against the seller because the seller breached the contract by sending your company t-shirts instead of shoes.
If you cannot resolve this through negotiation, then you may want to try mediation (an independent person tries to get an agreement between the parties) and if mediation does not work, you should have a strong contract case against the seller and against the buyer as the buyer's claim is not against you (assuming contract language with you being the shipper), but against the seller. Good luck.
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