You’re at risk of some over zealous prosecutor accusing you of structuring.

It’s not the $9k deposit that’s illegal, it’s structuring your deposits to avoid the $10k limit. The same actions can be legal or illegal depending on your in intent.

In your example, the $9k deposits are perfectly fine. Although if you really always deposit $9k you’ll probably get some questions.

like tax evasion laws -- they're like a joker card/ wildcard -- to law enforcement. to be played when they wanna arrest you.

that's what mobsters get nabbed on, corrupt gvt officials etc. it's not difficult to prove anyone has tax evaded.