As a former forensic/crime scene photographer who was doing the work at the dawn of digital, I can say that on one hand I understand his perspective. On the other, using a photograph in court requires the photographer (or the person having it entered into evidence) to swear that it is a true and accurate representation of the scene as he/she saw it at the time, so the reputation of the photographer is at stake if it's manipulated. Back in 1996 when this whole issue first surfaced and I was running a crime scene unit/crime lab in NoCal, I was absolutely opposed to switching to digital, while a good friend of mine (with whom I am still in touch) in the Seattle area was on the cutting edge of adopting it for crime scene work. We had some great discussions in those days. I knew that digital was the next big thing, but I was able to play devil's advocate for film for a long while.
Now, that said, I've photographed crime scenes that were physically manipulated by suspects, witnesses, and cops; either intentionally or unintentionally. So my sworn testimony that the photo was a true representation of the scene as I saw it at the time still doesn't mean it was an accurate representation of how it was when the crime occurred.
And then, of course, there's the issue of manipulating the image through perspective, angle, and composition... what I chose to include in the photo and what I chose not to include, or block out through angle or perspective; something EVERY photographer does... and is entirely subjective. And there has been darkroom manipulation since the beginning of the photo process. Digital just makes it easier for more less-skilled scene-manipulators to make their manipulations after the fact.
There's a LOT of philosophical discussion that goes on about this issue even today. Really, the whole thing boils down to the credibility of the photographer offering the photo as "an accurate representation of the scene as it existed at the time of the photo" rather than the anti-manipulation limits of the medium used to make the image. I will say, however, that since digital imaging and digital manipulation has become so commonplace, that the general public is more skeptical of "truth" in imaging than they were thirty years ago. If there's an allegation of manipulation, the public is more ready to believe the challenge than the photographer and that makes it tough for folks like McCullen and working crime scene photographers to authenticate their images.
