Let me throw in my $.02. The government I'm pretty certain has the technology to access any part of our smartphones features if not at least most. Recently my iPhone 5 started acting up, very strange things it was doing. The camera light would turn on, music would start playing by itself, applications would open and I would always find started emails, with populated scribbles on the to, subject and header fields. Is is of someone that has access to these feature was having a fit doing this, just for fun. It is very scary, I had to reset my phone, did a clean restore and in the process lost a lot of information.
So I'm pretty sure these federal agencies have access to these features like in the likes of FBI, NSA or even the new TSA a agency. Remember these people operate in secrecy and have secure access to all these technology the average Joe like us doesn't even know it exist, but based on all these new spy leaks recently, we are aware specially the government is spying on us and we have all the reasons to be more paranoid than ever, the OP has a point with the camera access feature.
I have been thinking about just carrying an old palm OS handspring visor that has no access to wi-if or Bluetooth and no GPS. I'm no one important, but anyone and everyone should take their invasion of their own privacy very serious.