The startling image of Kathleen Peterson lying at the bottom of a staircase at her home in Forest Hills, North Carolina leaves a lasting impression. Soon after her death, in 2001 her husband Michael Peterson was arrested for her murder with French filmmaker Jean-Xavier de Lestrade documenting behind the scenes of his trial with defence lawyer David Rudolf. The Staircase observes the inner workings of the American Criminal Justice System leading the viewer on a thorny investigation that has lasted for 16 years.

Rudolf has specialised in high-profile criminal and civil rights cases for over 25 years and will be touring the UK over the next few months to speak about the greatly publicised case. The thought of interviewing him is intimidating. He's professionally trained to debate and could easily poke holes in any line of questioning. Rudolf is eloquent and to the point in his answers as we speak over the phone. There's no hesitation but there is emotion as I ask him how difficult a decision it was to no longer represent Peterson after the retrial in 2011. He sighs heavily and says, 'The decision wasn't difficult because of the circumstances that I found myself in and because of the emotional toll this case took on me. In terms of talking with Michael, I didn't want him feeling like I was abandoning him.'

From watching the series you can see how invested Rudolf is in the case, but what were his worries about allowing a crew to film him? 'My concerns were pretty much attorney/client privilege concerns and about the prosecution being able to get a hold of our strategies before the trial. We took certain steps to protect ourselves against that. We agreed that any of the film would be sent immediately over to France, so the prosecution would have to go through international procedures to get that footage back.'

The Staircase has now officially wrapped but features a revelatory interview with the presiding judge. Rudolf explains how he felt watching that footage, saying, 'It was surreal to me for two reasons. I thought it was very courageous for Judge Hudson to admit on camera, that he may have made a mistake in his legal rulings and at least the way I heard it was that he had a reasonable doubt about Mr Peterson's guilt. I think both of those things were both unusual. I had never seen a judge so candidly talk about a case that he had presided over. On the other hand, I sat there and thought to myself, this is a little bit late for me and for Michael. Why didn't you listen to our arguments 15 years ago when they really would have mattered?'

Staircase is available on Netflix now. An Evening with David Rudolf, O2 Academy, Glasgow, Thu 18 Oct & Mon Nov 26; Queens Hall, Edinburgh, Sun 25 Nov.