jalima I've watched last night's again (saddo that I am) and, to me, it does NOT appear that Daryl is confessing to the murders, as such. I believe, though, that he is connected to the final murder, and knows that his car -or a red car like his-has been seen by a witness in the area at the time of the latest murder. The police have his dna from the attack he made on the thugs who were taunting him earlier in the series. However, I don't think we've been told what the modus operandi of the final murder was (I may have missed this).
On reflection, I don't think it would be possible for the mother to shoot herself with that rifle. I think there's more to the shooting than meets the eye, though. I loved the (rather subtle) blood spatter on the window at the end too.
I was wondering about the van too, jalima. Nevison would have had access to it, presumably, while Sean was in his employ. The police would've too, of course, during their search for dna. So John may have planted evidence; is it possible that another officer eg Anne, could also have done so?
And what is it about Nevison and Anne that's unsettling? Is it the saintly, mourned wife, the fact that Anne had a drink problem? Something's definitely not right! And the relationship he has with Catherine is definitely unhealthy; I think she's foolish to encourage it, from a professional point of view. I like your theory about a possible motive! I can't see much point to Anne, or Nevison, really, in the second series if they're nothing to do with the plot.
And Neil! He's been blackmailed by one of the victims, he won't go to the police, he's capable of uncontrollable rages and he's afraid of Catherine. Very odd. DD has a theory about his working in the supermarket; that he's somehow linked to the "biscuit factory", and the trafficked girls. There must be a point to the girls, the murder of tasered bloke and the mentioning if the Knevevics (?) at regular intervals.
There's a lot to be crammed into the final episode; can't wait!