He is thought to be responsible for 13 murders, 50 rapes, and 120 burglaries.
He feigns incompetence, as if perhaps he is experiencing dementia in his old age.
Most people then referred the this killer as EARONS.

However, some people familiar with the case also liked EARONS as the suspect for the Visalia ransackings.
The couple may have confronted DeAngelo while he was prowling or peeping.
From 1976 until 1979 he worked as a police officer in Auburn, another small town near Visalia.

In 1979 he was arrested for stealing a hammer and dog repellent and fired from the police department.
He eventually began a new career as a truck mechanic.
This is a common tactic police use to cover up actions of fellow police officers.

Police sketches of the suspect,FBI
This is called theBlue Wall of Silence.
His ex-fiance (the infamous Bonnie) said that sex with DeAngelo was painful and exhausting.
She said Joe was a poacher, a thrill-seeker and an illegal hunter.

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After they broke up in 1971, DeAngelo showed up outside Bonnies bedroom one night with a gun.
Bonnies parents were home and her father got a gun only to discover DeAngelo was already gone.