It depends how it works, as I should imagine that with the right keyworkds that google could be manipulated into finding illegitemate material, but the owners and maintainers of google don't have that much control over it as the engine itself just scours the web for keywords and puts them into it's database.
If they were to disclude words such as "illegal" then many places like law firms and so on wouldn't be included in their crawls.
But if it's submission based, ie: you send a site (or ftp in this case) to the owner, and they review it, then add it if it's ok.. then they could get into trouble as they have approved whatever content is on the ftp.
