Crime scene: 162 mystery solving puzzles to find out who the murderer is

Chapter 30 The Trick That Was Detected
One summer night, Wilson died in his study.Holding the pistol in the right hand, a bullet hit the head.There was an electric fan and a suicide note on the table, which stated that he committed suicide because of the unbearable loneliness after being widowed, and rushed to heaven to meet his wife.

Officer Crews was at the scene and saw the electric fan's cord had been unplugged from the wall socket. "Did Wilson knock it over when he fell off the chair?" Cruise had a hypothesis in his mind.Just to be on the safe side, he plugged it in, and the switch of the electric fan was on, so it turned again.

Officer Crews had a clue in his mind: "This is not a suicide, it's a homicide! After shooting Wilson, the murderer put the fake suicide note on the table and fled the scene." Why did the police officer make such a judgment?
[Answer] Plug in the plug, the electric fan starts to rotate, and the suicide note on the table will be blown off by the wind.And that suicide note was still on the table when the body was found.That is to say, when Wilson, who was shot, fell to the ground, he touched the power cord, the plug fell out of the socket, and the electric fan stopped turning before the murderer put the fake suicide note on the table.There is no doubt that it was homicide.

(End of this chapter)