I never intended to be a documentary filmmaker. I think I became a documentary filmmaker because I had trouble writing, and I had trouble finishing things.

It's so much easier to make a movie about someone who is so likeable that you just want to get out of the way.

Maybe [killers] is one of my real passions. Why deny it?

I used to work as a private detective years and years ago. And my boss gave me this one very simple piece of advice about trying to figure out who to interview first in any investigation. His recommendation: Always pick the people who were fired. Pick the people who are pissed off.

Nothing is so obvious that it's obvious.

Finding truth involves some kind of activity. As I like to point out, truth isn't handed to you on a platter. It's not something that you get at a cafeteria, where they just put it on your plate. It's a search, a quest, an investigation, a continual process of looking at and looking for evidence, trying to figure out what the evidence means.

If you want to trick someone with a photograph, there are lots of easy ways to do it. You don't need Photoshop. You don't need sophisticated digital photo-manipulation. You don't need a computer. All you need to do is change the caption.