Civil asset forfeiture cases in the US, insanely, have a reversed burden of proof and are in re actions against the assets to be seized. When assets are seized by law enforcement, you have to petition for them to be returned and prove that you came by them lawfully. You don't ever need to be convicted of or even charged with a crime in order to have your assets seized.

I don't know anything about how long law enforcement has to wait before selling your assets.