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How to properly store seed phrase during inspection? Cops need suspicious reasons to inspect someone else. If the person has suspicious activities, he or she should be more careful on how seed backups are stored.
Instead of writing seeds to paper and easily be seen, they can backup it in a book.
Choose 12 words in first pages of a book for their seed backups and write number of pages on a paper. Cops will not check it.
If a person is suspected and the cops found those numbers written on paper, I am sure cops will be curious and make their way so that the suspect will cough out what is in that numbers. Then eventually the passphrase will be revealed, it would take longer though.
It is always best to not bring your written seed phrase around. You can bring your USB or HDD where your seeds are saved make sure it is encrypted, in case it is inspected they need you for the password or they can Bruteforce it which may take too long, and at least your private key and seed phrases won't be exposed in public accidentally.