Is having a bong against the law?

i know obviously that if you smoke marijuana out of the bong than it is illegal, but what if it's brand new and never been used. can a person argue that the bong is used for other legal purposes aside from smoking marijuana? i heard chong got arrested awhile back for selling bongs online, or something like that. i mean, can they really arrest you or cite you for having a piece of gl shaped a certain way?