We are losing track of the conversations- I think you have asked me that question a couple of times now
I 100% agree that MP is a jerk, I have no idea if those texts to his sister were typical or not, internal affairs will find out.
I did not see any evidence that he planted any evidence, only speculation that he did. Lots of sloppy police work, but enough. Once you buy that the evidence is the evidence its simple.
Therefore, the tail light pieces at the crime scene could only have come from some sort of collision. The plastic fragments on his shirt indicate he was the thing involved in that collision as well as his DNA on the car. His phone GPS that says he never moved, never moved. The lack of canine DNA on the right sleeve of his shirt cinches that no dog nibbled on his arm. She likely scratched it. The mechanism of his death that night will never be known but there are reasonable things you can imagine if you buy into that evidence was not planted.
I don't think she has any memory of this and was likely not even aware that it happened. Based on her blood alcohol levels she would have been on the verge of passing out and so would JO. She's a highly intelligent and accomplished person who, once more sober, put the pieces together that morning and realized what had happened; thus the panic and the confession at the scene.