Murderer
The suspect who killed the victim. Proven by the murder condition after all placements.
Explanation
The murderer is determined last. After all suspects are correctly placed, check which suspect is alone with the victim in the same region. That person is the murderer. You cannot determine the murderer before all positions are finalized.
Example
After placing all 8 suspects, you find that only Max shares a region with the victim and no other suspect is in that region. Max is the murderer.