I think we can definitely correlate crime levels to one thing, and I think we've reached consensus on it.
Walter Lantz's "Woody Woodpecker."
I would note that as the 1980s wore on, Woody Woodpecker was being shown less and less on television. America, in its Chilly Willy-less-ness, was going into the crapper. The crack epidemic. AIDS. And so on.
Eventually the amount of Woody Woodpecker on in the afternoons dropped to zero. I was crushed. I know that I was entertaining ugly thoughts in my head.
So why did crime start to drop in the 1990s?
The Internet made Woody Woodpecker widely available, at first on FTP sites, then P2P services, and today, via BitTorrent and so forth. As Woody Woodpecker returned to public consciousness, crime plummeted.
That's all it is. Woody Woodpecker, bro.