Where does "sagging" come from?

by drunkpontiff

There's a popular probably myth that sagging originated as a way for prisoners to signal that they were "homosexualy available". Others say that while it did start in prison it was due to ill-fitting clothes. Can't find any good sources online for either theory or any other. Anyone have any clue how this fad got started?

Xenothing

20 year rule applies to this I think, unless someone can show otherwise.