can anybody provide me the answer to this question:
mystery case: one sunday morning on a condo unit a man found dead with a gun on his hand and a recorder on the other, the boardmate immediately called the police. on the crime scene: (no struggle no force entry) the detective in charge played the tape recorder "im tired of my life i want to die (gunshot)" and he ask the boardmate if that was his voice and replied YES! then the detective said: we must find the murderer
how did the detective know that it was a murder and not a suicide?