minimus - "Why doesn’t Watchtower simply follow the laws of the land and report immediately to the proper authorities?"
Probably because if they did, and a significant number of offenders ended up being successfully prosecuted (and it's pretty clear by now there's a very significant number), they'd become "known" abusers...
...and by the WTS' own stated internal standards, "known" abusers cannot hold congregation positions (even after they'd quietly lightened up on related restrictions a few years back).
Not only would a lot more JW parents start skipping out to keep their kids safe (not to mention closing up their wallets), but really, who the fuck would even want to go to a KH where known sex offenders attended?
I strongly suspect that pretty soon, they'd be experiencing a serious barrel-bottom-scraping shortfall of vital "qualified brothers" needed to run the Org at the grassroots level (something we tend to forget)...
...which could - depending on the scope of the problem - seriously cripple the religion's ability to function...
...which would, in turn, potentially place the WTS' survival at risk.
And from their POV, they simply cannot allow that to happen...
...so they keep doing the wrong thing, even though it will (ironically) probably result in a similar outcome.