You’re a bit of a police procedural perfectionist. How much did you change?
Without being critical of the writers, because they were more interested in getting the story straight, I did. With my experience of the FBI - my dad was an agent and I know how they think and work - and my knowledge of the Internet through my teenage daughter, pus police procedure from the TV shows I worked on over the years, I knew it wasn't right. So I enlisted EJ Hillbert, who is head of the cyber crime unit in Los Angeles, to help me correct it.
Are you afraid of giving crazy people ideas?
We have a tricky moral responsibility with the movie, but the fact is this stuff is going on. There are 300 million streaming videos per day in America. That’s nine billion a month. In Mexico, some of the drug gangs are streaming executions live to stop people from testifying against them. Untraceable is a cautionary tale and we're trying to make people more aware of what can go on.
Would people really watch someone die online?
Oh, yeah. We used to fill a coliseum with people watching Christian get fed to the lions. And in France, people would gather to watch people's heads being chopped off and have a party. We're just at the contemporary end of that. In the making of the movie, some of the researchers would get me things to see and I was appalled.
Have you become more careful on the 'net?
I use it for email, for writing and for news only. My daughter is out there in the universe and we watch her very carefully!