Cannot "arrest" something that's not a natural person, but yes, they could absolutely seize a bot under a number of civil forfeiture laws, or likely as evidence. The burden would be on the owner to sue to get it back.
I've always heard that with civil forfeiture they are "arresting the money". Isn't that arresting a non-person? Or have I just been reading simplifications?
Simplifications. "Arrest" has specific meaning in most jurisdictions. "Seizing" would be more appropriate; one can seize property as well as persons, and in the case of persons there can be a seizure without an arrest.
The point is what a designation is for; in the case of an arrest vs detention or seizure for natural persons, it's usually an elaborate shell game around when various search doctrines or other restraints on police behavior kick in. In the case of property, the only point is to grab your stuff; the circumstances surrounding it don't particularly matter because they can always decide later under one doctrine or another that they're entitled to keep it.
