A very horrible thought... ("He: means JP)
He purchased propane.
He had a cutting torch.
He purchased large amounts of plastic tarping/sheeting.
He had damage to the skin on his hands.
He left with Susan, and she didn't return.
It was freezing that night (or lower).
He had some mileage on the rental car (between 200 and 1000; I'm thinking it was around 250 or so, or LE would've released close to 300, iykwim).
SP has been arrested in WA.
SP is being considered a POI in Susan's murder.
He has a storage unit in WA.
Putting that together, it may be that:
JP murdered Susan, used a propane torch to dismember her, wrapped her dismembered body in separate plastic sheeting, gave the wrapped packages to SP at about 100 miles or so from the house in Utah, SP came back to WA and put the wrapped plastic into a storage unit which had been rented either under an alias, or under JP's name, but definitely not under SPs name.
This would account for all aspects in the first part of my post.
Susan may not be found in mines or in searches because *she's not there.* I've been thinking while these two were utterly and completely evil, they were also fairly canny, and were aware of jurisdictional issues and the inability to search privately held property (rental units, storage, home, PO boxes are considered privately held property as long as the bills are being paid). Because of jurisdictional issues, Utah LE is unable to search the WA storage unit; and WA LE can't search because there was no crime yet that was in the person's name that held the lease to the storage unit.
This whole thing sickens me...but it accounts for everything we know as of now. Doesn't it? Or am I missing something?
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Herding Cats