You will never know till you visit.
The police only attack you if you deserve it. Very few will antagonize inocent people. Mexico is like many other countries, there will always be place you should avoid.
The news has no idea what goes on with situations in other contries like this, its all speculation. It's amusing actually... as if cartels were best of friend untill recently. None of this is news.
Mexico is a beautiful country with every kind of senery you could possibly want yo see. From snow, to desert, to mountins, to jungles, to beaches. If you go enjoy, and if you like ask where to go and where not to, Im sure you'll be helped.