maybe a bit specific, just finished the game after forgetting about it for years, and kinda got hooked in the Ghost inspector theme (i know there are other video game with that plot, but im sure there must be novels, with how popular murder mystery books are)
by Baron_alias
1 Comment
Odd Thomas by Dean Koontz sounds close to this. Main character is the medium though and he works with the detective. And not his own murder.