Generally speaking, no, but it depends on what circumstances you are referring to.
You cant.Its illegal to have one in California
Yes it is illegal to own a gun that does not have a serial number. It is also illegal to remove the serial number off a gun.
if a gun has a threaded barrel, (required for a silencer) it is classified as an "assault weapon" and is illegal in California.
You can't. Owning a ferret is illegal in California and Hawaii.
It is not illegal to own ammunition but you must have a permit to own a gun.
yes it is illegal to own a sawed off shot gun in pennsylvania...as far as i know its illegal in every state of the US
No
No
Yes, it is illegal everywhere.
No.
No
No,sloths are illegal. Sorry, you have to own a permit to own a sloth in the state of California.