This summer, Mackay confessed to NewsChannel 3 from jail that he and his mistress, Nicole Houchin, were plotting to kill his wife, Dana Mackay, but he never thought Nicole would actually do it.
John and Nicole are both charged with Dana's murder.
In court, an investigator took the stand, and said during an interview with Mackay after Dana died, he admitted that he was willing to pay anyone $20,000 to kill his wife.
The officer also added, in that interview, John said after Nicole told him she killed his wife, he responded, "that's wonderful, and I'll love you forever."
The same investigator testified that he found hundreds, if not thousands of emails between John and Nicole. Some of those emails said how they plotted to kill Dana, and how they could make it look like an accident.
In our earlier interview with Mackay, he says he never thought Nicole would actually go through with the murder.
"Did you anticipate that she was in any way going to go through with that?
No, no, this was all just a talk, bulls***, we had talked about leaving, we had talked about a bunch of times and running off but nothing ever happened. Nothing ever went anywhere after that and then I was like, it happened," Mackay told NewsChannel 3.
Friday in court, the officer said the day he found Dana's body in her bedroom, there was blood all over the walls, and she had several wounds on her face.