Could he
I think your hypothesis is consistent with the evidence we know and on point. One question remains for me and that is the role of an active accomplice, one who dropped FD off at Jennifer's home and later helped move Jennifer's body. Could FD himself have parked the red truck, with the doctored plates on them at a nearby, secluded location before traveling to Jennifer's home to ambush her? He then walked to JD's home through the woods, once again avoiding security cameras (which, by the way is evidence of premeditation).
I have zero doubt he was waiting for her when she arrived home, and he killed her in the garage. He left evidence there because, despite his belief in his superior planning skills, he did not intend to leave an actual bloody mess there. He must have panicked, because why else would he have so stupidly washed his hands in the kitchen sink? At every step, he was not the mastermind he thought he was, but then, what else is new?
After murdering her, he transported Jennifer's body (which was rolled up in the carpet) in her SUV to that secluded location. There, he placed her in the bed of the truck, still rolled up in the carpet. He then left the "carpet roll", or even her tarped body, in the red truck ,and drove Jennifer's SUV to the park, where he left it as part of his PRE-PLANNED Gone Girl scenario. He then returned through a wooded area to the secluded red truck. His walks in the wood explain the poison ivy rash observed during his arrest, which he cannot deny. In fact, I believe he may have traveled through the woods as a way to avoid being seen more than once, so he could have been exposed to poison ivy more than once. He took affirmative steps to avoid direction by traveling through at least one wooded area, and those steps were planned in advance by him.
Jennifer's body was in the back of the truck, which we know to be true, because why else did FD take the trouble to have the car professionally cleaned before returning it to his employee? This scenario also explains the altered plates. He left put those plates on the truck before he parked it , so that if a witness ever remembered it s/he would remember a bad tag number, thereby preventing LE from connecting that tag/truck to him. I have felt since day one that the red truck's movements on that day are critical as is that poison ivy evidence.
Once Jennifer's car was where it is supposed to be, FD has all the time he needed to begin whatever sick s*** he did to her body in order to dispose of it. We further know whatever that was involved a knife, "lots" of blood (the witness said he saw a large amount of blood on the pillow he saw), garbage bags, a bloody pillow, bloody sponges, mops, stripping JD of at least the bloody shirt he murdered her in and, of course, FD's jaunt to Albany Avenue, accompanied by MT. While LE may not have an actual body (they do not need it to prosecute FD for first degree murder), it has plenty.
The employee from whom FD "borrowed" the truck has already provided pieces of the puzzle IMO. Do not be surprised if he helped load the garbage bags into the truck. The location where that occurred will have significant forensic evidence. IMO the location where those bags were loaded is where FD took Jennifer's body.
What FD, in his arrogance, did not consider, is the speed with which LE would act. Getting that phone at the police station was critical. Despite NP's crudely drafted motion to suppress evidence of the phone's seizure, there is not a judge in this country who would hold that its mere seizure was a violation of the Fourth Amendment. In fact, there is United States Supreme Court precedent which explicitly rejects such claims. LE got a warrant to search that phone (or, as the Court called it "mini-computer") and it was a treasure trove. The actual forensic search of it was from the Marshal's Office, who are the most diligent group of professionals one will every meet. The FEDS were in the case from day one, which is a very, very good thing. It means task force, it means all of the resources of the federal government are helping solve this crime, and it means FD is going to prison for the rest of his life.
I believe FD had at least 2 accomplices - MT and the lawyer who was to provide the false alibi. I wonder if that alibi was concocted before or after the murder, not that it matters for purpose of prosecuting him. IMO, in light of what has now come out about that "sterling" example of the legal profession, NP would absolutely enrage people on the jury if he tried to present the attorney's perjurious testimony to them as some sort of alibi defense. The guy is completely discredited as a witness. Plus, he is already on the hook to be criminally prosecuted as an accessory and a possible co-conspirator to this murder. He will absolutely open himself up to perjury and obstruction of justice charges if he continues on his ruinous path. The last two offenses can be charged a federal felonies and the feds don't play. If have seen 5 year prison sentences for perjury in cases far, far less significant than this one.
So, now it is a matter of how many people did FD pull into this premeditated murder beforehand, and what were their respective roles? Some people are going to be more criminally culpable than others, at least based on what we know now. Some people may not have even known what he was planning before the actual murder and did not knowingly assist him in covering his tracks after the murder, but they still will be able to narrow his location and activities on the day of the murder significantly. Some people may have become involved after the fact, but nonetheless have criminal liability because they were aware of, and assisted FD in disposing evidence of this premeditated murder. IMO all the concocted evidence that FD thought he was so cleverly creating, before and after this horrendous act, will not save him. Tick, tock Mr. Dulos, your time as a free man grows shorter by the minute.
Would love to hear other theories, but I think the posters here are closer to the truth than we know. Does anyone have any ideas about where he might have taken Jennifer's body between the murder and his trip to Hartford? I am so very hopeful LE already has the answer, but am curious as to what other folks here think.
