A prime suspect or key suspect is a person who is considered by the law enforcement agency investigating a crime to be the most likely suspect.
[1][2] The idiom "prime suspect" is believed to have originated in 1931.
[1] "Key suspect" is seen as early as 1948.
[3] There are various reasons a person may be considered a prime suspect.
[citation needed] These include: This law enforcement–related article is a stub.