maybe one of the backers of winter petroleum?
What's the theory? Was the accused set up, was he involved with a biker gang that murdered a five year old child and his grandparents as a favour, or did he get together with someone that lost money through dealings with one of the victims and together the committed murder?
What evidence is there that more than one person was involved in the three murders?
Is there any evidence that the murders are a result of business dealings? As far as I remember, the evidence led to the accused, and only then was a possible motive understood. It isn't the case that the motive was understood, and therefore someone with business dealings was arrested.