that's not what premeditated murder is though. That's trying to cover up the murder which is also a crime, but a far cry from premeditated murder which is one of the most heinous crimes recognized by the legal system.
Which is why I said I don't believe the murder was premeditated.
He was able to plea to second degree in exchange for the location of the body and essentially a confession.
They convicted him of first degree because without the body, there was no evidence that he didn't plan on the murder as well. Ironic in a way. He hid the body to try and hide the evidence that she was dead, but turns out that only made things worse for him.
If he had called the authorities and copped to it as an "accident of passion", he'd probably be out by now.