Well, I don't know much about the statutory rape laws, soooo...

But, I will say that in order for a pipe to be paraphrenalia the pipe has to have been used to smoke marijuana. There has to be residue (or resin) in the pipe from cannabis in order for it to be related to paraphrenalia.
An unused pipe is completely legal as long as you're 18, and, likewise, a pipe used for tobacco is also 100% legal.

A couple weeks ago I saw a guy just sitting uptown smoking out of a long peace pipe, dude looked Indian and I really had to question whether it was tobacco he was smoking. He was up there for about 40 minutes and no one, cops or civilians, ever asked him anything. I guess they figured it HAD to be tobacco if he was doing it right in public.

The only weird thing I saw is that when the guy left...there was a bit of a jump in his step, if ya know what I mean. So....yeah =)