Lord Hutton concludes that the knife found at the scene is one from Dr. Kelly's desk.
But the evidence for that conclusion is tenuous at best.
It seems from the first part of the following quote (which comes from Chapter 5 of the Hutton Report) that Janice Kelly was never, personally, shown even a photocopy of the knife.
Additionally, the identification of the knife (such as it is) is by hearsay in effect, with one of the supposed witnesses to identifying the knife, Ellen Kelly (or Wilson), having no witness statement on the Hutton Inquiry site that I can trace.
[1 September, page 53, line 22]
Q. We have heard about the circumstances of Dr Kelly's death and the fact that a knife was used. Were you shown the knife at all?
A. We were not shown the knife; we were shown a photocopy of I presume the knife which we recognised as a knife he had had for many years and kept in his drawer.
Q. It was a knife he had had what, from childhood?
A. From childhood I believe. I think probably from the Boy Scouts.
And in a statement furnished to the Inquiry Police Constable Roberts stated:
The knife found in possession of Dr David Kelly is a knife the twins, Rachel and Ellen recognise (from pictures shown by Family Liaison Officers). It would not be unusual to be in his possession as a walker. They have seen it on their walks with him. He would have kept it in his study drawer with a collection of small pocket knives (he did like gadgets) and the space in the study drawer where a knife was clearly missing from the neat row of knives is where they believe it would [have] lived and been removed from.
In addition, so far as I can trace, there is no oral evidence given to the Hutton Inquiry that the knife was used to incise the wrist, nor that it was sharp enough to inflict the injuries that Dr. Nicholas Hunt describes.
And there is, as far as I can see, no forensic science assessment of whether the shape and other characteristics of the blade were such as to cause the observed wounds on Dr. Kelly's left wrist.
The chain of evidence is astonishingly weak.