That's life!

Mark Twigg was over the moon when he arrived at the fence from Marcus's side. His satisfaction was compounded when told that Rufus had caught himself on the brambles. That meant Twigg didn't have to worry about official protocol to obtain Rufus's DNA. It was deposited during a crime... breaking into someone's property.

If his DNA linked to any of the murders, then even if the lawyers tried to bounce all over the police regarding admissibility of Rufus's DNA as evidence, Twigg would "do whatever was necessary" to ensure the boy went down for life...

"and I mean life!"