If the subject is no longer living, the immediate question is do you have enough first-person material to really get that story across. You'd like to avoid it just being other people's memories and interpretations.

I don't think that there is any hard and fast rule that says that documentary has to be linear at all.

I knew as a young boy that addiction and alcoholism afflict people - good, loving people - in profound ways, and that some people - usually from those rare "normal" families that I longed for as a child and as an adult wonder if they even exist - didn't understand this and sort of looked down their noses at people suffering with addiction.

The visual quality of the cameras now is such that you can shoot with available light, and if people are willing to mount a microphone on the camera and maybe even on the subject, then you're good to go.

You can just imagine the restrictions of shooting in a prison, but I just decided I'm going to embrace those restrictions sometimes when you don't have many choices you can make the best choices.

If I weren't making documentary films, I suppose I'd be teaching.

Documentary filmmaking has all the challenges and hardships of narrative filmmaking without any of the infrastructure or support. That's both a blessing and a curse.