He was arrested because he was asking too many questions about forensics etc -this cause alarm bells to ring, they took his DNA and surprise, surprise a match came up with the DNA found on the victims body! This would not stop me coming forward with information if I had nothing to hide! I never said you were disputing it, nor did I imply that you were.
So, is it suspicious to ask questions about the forensics? I recall the police were suspicious because he remarked about the front door being removed, and he was told it was "normal procedure". Well, I would have asked about that too, because I have never heard of that being done before, "normal procedure" or not! I am inquisitive, and I certainly would have been, had it been my next door neighbour who had been killed. As for the DNA, it had to be enhanced, and, from what I remember reading. the sample was used up in the enhancing procedure , so it could never be checked by the defence.
Therefore, I ask questions!