I'm not watching it, but there's a great article in the Radio Times this week by Ginny Dougary who interviewed Joanne Lees in 2006 and has in-depth knowledge of the case. It's written in an even-handed way, but highlights what an odd choice it is by Channel 4 to air this.
"The series consultants are disgraced former criminal defence lawyer Andrew Fraser, who once enjoyed a £100k a year cocaine habit and who served five years in prison in 2001 for involvement in cocaine smuggling, and his business partner Victor Susman who, in 2011, was quoted as saying 'This is just a great story. We see a book deal in this as well as the factual documentary. This is a fantastic opportunity.' They drive the narrative of the investigation, with the hand of Channel 4 almost visibly descending from time to time with counter-points in an attempt at balance."
A C4 dept head acknowledges the consultants are 'completely flawed characters. They would probably say that about themselves and also are unreliable in some ways' but still thinks it's ok for them to investigate this case.
The article goes on to point out that "in each episode, there are moments presented as fresh responses to an old case but which were, in fact, raised at the time and rejected as invalid."
The series looks at the possibility Falconio staged his own disappearance and was an expert in insurance fraud - but doesn't even say whether he had even taken out a policy on his own life or had one cashed in (the presumption is no, otherwise they'd say!).
C4 guy says 'there's a strong sense in Australia that there was something nefarious going on' and talks about how she behaved at the press conference. Dougary contacted a dozen Aus journalists and they all disagreed and one says that it's more suspicious for victims or witnesses of traumatic events to have perfect recall and stories that add up perfectly."
I also wonder about the rape & abduction charge Murdoch was acquitted of too.
Myself, I don't have any extra knowledge of this case but the way this article makes it seem it is in very poor taste imo.