I was just about to post a comment about David and the fact that I thought it was him but I decided to check and see if there was any new information. Was I surprised when I saw that they supposedly arrested David for the murder!
Ok, let's see if we can make sense of this. Maybe it's over, but maybe not.
1. Look back at the analysis of the note. All the anger and exclamation points and then look at David's interview with the PI and then at his interview with the detectives. Sounds the same to me. I think David wrote the note. He saw Monica at least three times around 1 a.m. in her office. That would be my guess who Monica was arguing with. He claims she was wrong to fire him after he hurt his back and blamed her for it. He also claims she owes him money. Was he the one who took the photos of the gambling? Monica couldn't have been the one to take the photos otherwise the Rep would have know about it and I can't see any of them wanting to play poker with her, much less take photos of them. I just bet that's what he claimed she owed him money for.
2. We knew that David was at his cabin and that both he and his wife said he was there very often fishing and hunting. It was very probable that David or someone that had been out there was where the soil came from in the crime scene.
3. He traded trucks with a guy that he hadn't known very long (who is of the same caliber) with $2000 to boot. He hadn't worked in a while so where did he come up with that kind of money? Had to be the money Monica owed him for taking the photos.
4.You can assume that this Morgan Prescott is the logical person to commit the murder because of the truck trade. He was a drinking buddy of David's so he most likely was out at the cabin. It is only the word of the two men that they swapped trucks. What if the real scenario was that David paid Morgan to kill Monica and the swap of the truck was only temporary? With all the cars in the parking lot that night, who would think his truck would stick out? David lives in Louisiana now so why would they suspect him, and if they did, he now had a red truck and the new owner of his truck also lives in Louisiana? Just the way David acted when the PI interviewed him, told me he either knew who did it or he did it.
5. @ kdcypress: the $10,000 was the amount of money that the Rep paid her in blackmail and she put the whole amount in the safety deposit box because that is the exact amount that she left in her will for her goddaughter. The Rep was trying at first to say he didn't know her to throw suspicion away from him but when he saw the photos Monica had, he couldn't deny it any more. He called her that because she blackmailed him and he couldn't let anyone know. I agree now that Lori was probably talking about David being the one that was threatening Monica. David slayed the giant so therefore this David wasn't living up to his name. The clown discussion was just that. There was a photo in Monica's file with a picture of Sidney the Clown and his pal Churro. We were tossing around the idea of whether it was someone in the case from a long time ago that she was going to do a story on or something. Apparently, if it was, it has no bearing on the case.
Now all that being said, I still vote for David because to me, it all fits. It could be that he paid Morgan to do it but David would still go to jail for hiring a hit man. Just like Charles Manson. He wasn't physically there when those people were murdered but it was at his direction that caused it so he is actually jailed on that charge but they'll never let him out because he threatens constantly that if he gets out, he will " continue his work."