DeAngelo's crimes were meticulously planned, often stalking his victims for several days and at times break into their homes to leave twine, which he would later use to tie up his victims. He made maps of the areas, and then watched the victims for weeks or even months, documenting their lives. He would usually break in before the rape or murder, unlocking sliding doors and window, and unloading guns. One victim reported feeling like she was being watched before the crime was committed.

After he stalked his victims to memorize their routines, DeAngelo left ligatures inside or outside the home to use as bindings for later. He also unloaded any guns he found and unlocked sliding glass doors or windows.

Before he became a rapist and murderer, DeAngelo was responsible for a series of burglaries in the northern California city of Visalia in 1974-75. The "Visalia Ransacker" took small trophies from the homes he broke into and also spent time going through women's clothing drawers. Many crime scenes had women's underwear scattered around the house.

In one chilling incident, DeAngelo concealed himself within a couple's closet, patiently waiting for them to drift into slumber. Once they were asleep, he abruptly revealed his presence, illuminating them with a flashlight. When the husband instinctively reached for a gun within arm's reach on his bedside table, the assailant directed the beam onto the bullets he was holding, revealing that he had already emptied the firearm.

Between May 1973 and August 1976, DeAngelo worked as a police officer in the burglary unit. He then he served in a different precinct, from August 1976 to July 1979.

DeAngelo was missing a section of one of his fingers, which he said happened while serving in the Vietnam War.

DeAngelo's bicycle was his get-away vehicle, allowing him to slip into the night silently and travel out of sight from cars and busy roads.

Legal issues arose for Dangelo in July 1979 when he was apprehended for the theft of a hammer and dog repellent. This incident resulted in a six-month probationary sentence and ultimately led to his termination from the police force in October of that same year.

DeAngelo would call and taunt his victims after the crimes - one recording released by the FBI had him whispering "gonna kill you, gonna kill you" in between deep sighs. He also called different police stations, claiming he was the East Area Rapist, cackling, then hanging up. Many times the would make the calls before attacks.

When police combed through DeAngelo's beige-colored house, they removed boxes of evidence, guns, cars a motorcycle and a boat. They also found 'trophies' DeAngelo kept from his victim's homes including jewelry, cuff links and necklaces with heart-shaped pendants.

DeAngelo would normally were a ski mask during his rapes and murders.

DeAngelo's initial victims were typically women who lived alone in single-family homes. However, as he gained more confidence, he shifted his focus to targeting couples. This change marked a significant departure in his methods, underscoring his growing audacity criminal confidence.

Upon stealthily entering homes and startling couples in bed with the beam of a flashlight, he would issue threats of violence against everyone in the house, including young children, unless they complied with his commands. His MO involved incapacitating the men before subjecting their wives to sexual assault. He would restrain them, placing them face down on the floor, often in separate rooms from the women. He would then stack plates on their backs, warning that any movement would result in the plates falling and lead to kill to their wives. This cruel tactic forced them to remain completely motionless.

Unsealed court documents reveal that investigators in the Golden State Killer case were actively seeking gold jewelry, keys to a residence, and a Chinese gambling chip that had disappeared from a Ventura residence following two tragic murders in 1980.

DeAngelo often would take breakings during his attacks and help himself to some snacks - eating crackers or apple pie, or would stop and drink a beer.

Former co-workers described DeAngelo as “a regular Joe,” with a serious demeanor and nonexistent smile. They remembered him as a meticulous homeowner, with a love of candy and sweets, and even called him 'Junkfood 'Joe.' They were shocked when he was charged with unspeakable crimes.

DeAngelo wore black tennis shoes, size 9, and as the investigation into the sexual assaults continued, detectives would find the same shoe impressions under windows at every crime scene. This allowed them to link the home invasions to one serial rapist.

DeAngelo's was the first public murder case to use family tree forensics In the early 2000s, investigators were able to obtain DNA from the unknown killer at one of the crime scenes. They then started reviewing rape kits -- which contained DNA samples from victims where the alleged crimes spanned 10 counties.

One of those counties was Contra Costa, where a recently retired investigator plugged the mystery killer's DNA into a genealogy database.

Based on the pool of people on the genealogy website, investigators were then able to build a family tree of the unknown killer’s relatives.They narrowed the search based on age, location and other characteristics, eventually leading them to DeAngelo.

Authorities surveilled DeAngelo and collected his discarded DNA from a tissue left in the trash. About six days before DeAngelo's arrest, investigators plugged his discarded DNA back into the genealogy database and found a match, linking DeAngelo's DNA to the DNA gathered at multiple crime scenes, she said.

When DeAngelo appeared in court for the first time, guards pushed him in while in a wheelchair, looking frail, pale, and weak. However, many doubted his sincerity. Not too long after he was sent to prison, video emerged of DeAngelo exercising and even climbing on the furniture in his jail cell, solidifying everyone's suspicion that he was still up to his manipulative pschopathic behavior.