I think they did treat it like a crime scene after the first couple of hours when it became clear Deorr wasn't going to found right away. People can breach crime scenes and do.
The sheriff’s office issued a news release Sunday night, which reported “a comprehensive search of a radius of 2.5 miles from the campground has been completed by Search and Rescue staff.”
The sheriff’s department reports one huge hindrance has been folks showing up on their own and entering the search area without the incident commander’s knowledge.
“The Lemhi County Sheriff’s Office is discouraging concerned folks from entering the search area without being requested as we cannot keep track of who is in the area,” officials said in the news release. “… The reason for this is the area is very steep and mountainous, and the need to keep track of ground resources is paramount in case someone is hurt or otherwise needs assistance during the search.
http://www.eastidahonews.com/2015/07/grandma-of-missing-2-year-old-he-just-vanished/
BBM ETA: First sentence, showing this was still a problem Sunday night. The search area was not locked down until then, so people were coming and going as they pleased. It may have been treated as a crime scene from that point onward, but even a few hours of the area being unsecured after DeOrr disappeared could have done irreparable damage to any "evidence", tracking or criminal, in the area.
OT: Does anyone know how to tell if their inbox is full before someone tries to send a message? Is there a limit on the number of "visitor messages" a person can have on their profile page?