Engaging in a speculative narrative!
Conspiracy: No way!
What about this scenario (moo): It's my understanding that the couple were arguing that night and drinking heavily.
Maybe when he (JO) exited the vehicle he hits the taillight (or she backs the vehicle into him/he hits the taillight w/fist), he slips and falls down. The fall causes the head injury and arm abrasions depending on what he has fallen on. KR hears a loud thump from him hitting the taillight, but leaves anyway. Later she thinks more about it - starts to question things - may have hit him(?), which is why she makes numerous calls trying to reach him. However, by then it’s too late.
I'd be interested to know what the weather conditions that fateful night was, and how much snow, if any? How much ice? What were the surrounding area, can't fathom how the hit/fall would take place. Looking forward to the trial, curious what evidence there is. All moo and no factual information.
Trying to follow in your same order.
Karen and John were known to have a tumultuous relationship. She has said as much, as has at least one of John's kids. But there is no indication they were arguing that night. They can be seen in the CJ McCarthy's video hugging each other. Karen did leave some angry voice mails for him when he didn't answer his phone after she says she thought he was in the house. Either because she thought he blew her off or maybe even was cheating on her. (my speculation)
Have you ever tried to break a modern taillight with a fist? It can't be done. It's also hard to break a taillight with a human body going 24 mph backwards, although that is the state's theory. I'm not a biomechanical expert, so I can't say whether it's likely or not. But I'm sure both sides will have experts to address this. And as far as the state's theory goes, I'm at a loss as to how she backed into him and somehow managed to knock him 12 feet - sideways - onto the lawn. There were no tire tracks found on the lawn.
The head injury is what killed him. Coupled with hypothermia of course, but it's what incapacitated him. It's actually fairly small, but deep. I'm not sure what could have caused it on the vehicle, on the street, or in the yard.
I know the ME called the arm injuries "abrasions" (she was told by the police that he was hit by a car in the street) but they clearly aren't. Google "abrasions". They're rubbing type wounds that some might call scrapes they tend to be clusters. John's injuries looked nothing like typical road rash. They're deep scratches or lacerations spread out up and down his arm, mostly going in the same direction. I can't think of anything outside that night that could have caused those wounds in that pattern. Some are speculating they were caused by canine bites and/or scratches.
He had a lot of bruising the backs of both hands. If this was a pedestrian accident, I could understand bruising on one hand, but identical injuries on the backs of both hands is harder to understand.
Yes, it was snowing but it hadn't yet accumulated much. The blizzard was supposed to intensify overnight, but it didn't get bad until just after daylight. (I remember it well. I live a few miles from the house and we ended up with almost 2.5 feet of snow).
Worth noting is that the first snowplow pass on the street made by a town DPW employee was at 2:30 am and then again at 3 am. The state police never bothered to track this driver down. When he was finally interviewed over 1.5 years later he says he absolutely would have seen a body on the Albert's lawn at 2:30, considering the height and lights on his truck. He went on to say that at 3 am there was a light colored Ford Edge (not Karen's black Lexus) parked on the street directly in front of where the body was later found. He remembers this because he was annoyed there was a vehicle on the street at that time.
Along this same lines, there were several party-goes who left in separate vehicles after John was supposedly left on the lawn. No one says they saw him there.