Yes i agree. I also think its a possibility he murdered them at their home, not even necessarily in the house either. If he subdued the victims in whatever way he did that, with a weapon?, then if he had premeditated these murders, he could of even killed them in the garage with tarps? That way there would be no blood evidence left behind. He could of even lined the back of his vehicle with one, so again no evidence there either.
I base that theory on the fact of the shop towels which were in the McStay garage, and a white shop towel in the grave with the blue painters tape.
(quote)
There was a blue painter’s tape that was in the white shop towel, in the grave. That white shop towel was consistent with the roll of shop towels that was found in the garage.
Excerpt from Prelim. Pgs 47 – 49 (Detective Joseph Steers)
