I think both..have your own trail camera set up, and if you find anyone else's smash it, and take the memory card.I think it will depend on how big your operation is. If you have a handful of plants they will probably just destroy them but a significant amount that is worth their while, they may install cameras. I dont know what the magic number is but i would imagine if you had maybe 10+ in an area they might set up a camera. It has to be financially worth there while, setting up a camera for a few plants is kinda a waste of police resources when there could be bigger fish to fry.
If you find a camera what about just smashing the damn thing or remove the digital card or whatever recording media they are using and then never returning.
Or if you have the finances you could set up your own cameras and catch them before they catch you
i had a few cameras in a grow area where i was and see the red lights glowing in the dark and i took everyone of them and drop them in a hole in the swamp and left a note to beware of what will happen to them lol.. never had a problem at all after that and i had better cameras of my own set up.
That's why we have Cory and Trevor to do our dirty work.The newer cameras not only have gps but will email the pictures/video and/or a cloud service . Their around 600$ each but uncle sam goes for broke on our $ $ $
Stealing destroying the cameras is just asking for trouble . besides most times they would put up many cameras as insurance , and they conseal very well . If their found in the woods you can bet they will be on the road to capture your plate
The older / cheaper cameras , the IR bulbs glow slightly when on. red or green very vissible after dark
http://www.outdoorlife.com/photos/gallery/hunting/2012/10/halloween-photos-25-freaky-trail-cam-photos --- 30 freeky game camera shots , I got a kick out of this check pick15