The New York State Legislature enacted new statutes, known popularly as "Son of Sam laws", designed to keep criminals from financially profiting from the publicity created by their crimes.

During the mid-1990s, Berkowitz, by then professing to be a converted evangelical Christian, amended his confession to claim he had been a member of a violent Satanic cult that orchestrated the incidents as ritual murder.

[3]: 60–1  Berkowitz lived with his father while attending Christopher Columbus High School (graduating in 1971) and college in a four-and-a-half-room apartment at 170 Dreiser Loop in Co-op City from 1967 to 1971.

[25][3]: 76–79 Forensic anthropologist Elliott Leyton described Berkowitz's discovery of his birth details as the "primary crisis" of his life, a revelation that shattered his sense of identity.

He bungled his first attempt at murder using a knife, then switched to a handgun and began a lengthy crime spree throughout the New York boroughs of the Bronx, Brooklyn and Queens, seeking young female victims.

[52] In a March 10, 1977, press conference, NYPD officials and Mayor Abraham Beame declared the same .44 Bulldog revolver had fired the shots that killed Lauria and Voskerichian.

[66] As all of the shooting victims to date had long dark hair, thousands of women in New York City acquired short cuts or brightly colored dyes and beauty supply stores had trouble meeting the demand for wigs.

[74][75] Neither Lupo nor Placido had seen their attacker, but two witnesses reported a tall, dark-haired man in a leisure suit fleeing from the area; one claimed to see him leave in a car and even supplied a partial license plate number.

[74] With the first anniversary of the initial .44 caliber shootings approaching, police established a sizable dragnet that emphasized past hunting grounds in Queens and the Bronx.

[79][80][77] That night, Detective John Falotico was awakened at home and told to report to the 10th Homicide Division at the 60th Precinct station house in Coney Island.

[79] Local resident Cacilia Davis was walking her dog at the scene of the Moskowitz-Violante shooting when she saw patrol officer Michael Cataneo ticketing a car parked near a fire hydrant.

According to Mike Novotny, a Yonkers police sergeant, the department had their own suspicions about Berkowitz in connection with strange crimes in their jurisdiction which were referred to in one of the Son of Sam letters.

They saw a gun in the back seat, searched the car, and found a duffel bag filled with ammunition, maps of the crime scenes, and a threatening letter addressed to Inspector Timothy Dowd of the Son of Sam task force.

The initial search of the vehicle was based on the handgun visible in the back seat, although possession of such a gun was legal in New York State and required no special permit.

Berkowitz was briefly held in a Yonkers police station before being transported directly to the 60th Precinct in Coney Island, where the Son of Sam task force was located.

[3]: 11–13  After a brief and wordless encounter, he announced to the media: "The people of the City of New York can rest easy because of the fact that the police have captured a man whom they believe to be the Son of Sam.

In a letter to the New York Post dated September 19, 1977, he alluded to his original story of demonic possession, but closed with a warning interpreted by some investigators as an admission of criminal accomplices: "There are other Sons out there, God help the world.

[92][93][94] Berkowitz later stated in a series of meetings with his special court-appointed psychiatrist David Abrahamsen that he had long contemplated murder to get revenge on a world he felt had rejected and hurt him.

[8] In 1979, there was an attempt on Berkowitz's life in which the left side of his neck was slashed from front to back, resulting in a wound that required more than fifty stitches to close.

[124] He said that he and several other cult members were involved in every incident by planning the events, providing early surveillance of the victims, and acting as lookouts and drivers at the crime scenes.

NYPD officer Richard Johnson, involved in the original investigation, opined that unresolved discrepancies in statements from witnesses and surviving victims indicate Berkowitz did not act alone: Other contemporaries voiced their belief in the Satanic cult theory, including Donna Lauria's father.

[131]: 429–430 Journalist Maury Terry published a series of investigative articles for Gannett newspapers in 1979 which challenged the official finding of a lone gunman in the Son of Sam case.

[131] Largely impelled by these reports of accomplices and Satanic cult activity, the Son of Sam case was reopened by Yonkers police during 1996, but no new charges were filed.

"[40] Other skeptics included former FBI profiler John Edward Douglas, who spent hours interviewing Berkowitz and concluded he was an "introverted loner, not capable of being involved in group activity.

"[40] NYPD psychologist Dr. Harvey Schlossberg stated in Against The Law, a documentary about the Son of Sam case, that he believes that the Satanic cult claims are nothing but a fantasy concocted by Berkowitz to absolve himself of guilt.

"[135] Decades after his arrest, the name "Son of Sam" remains widely recognized as that of a notorious serial killer, with popular culture manifestations perpetuating this.

[138] Neysa Moskowitz, who previously had not hidden her hatred of Berkowitz,[136] wrote him a letter shortly before her own death in 2006, forgiving him for killing her daughter, Stacy.

[150] In 2021, Netflix released documentary series The Sons of Sam: A Descent Into Darkness, going back to describing in detail the Satanic cult theory as well as Maury Terry's investigations into the case.

[151] In the Seinfeld episode "The Diplomat's Club," Kramer uses the mailbag of David Berkowitz, owned by Newman, as collateral for a bet on airplane arrival times.

[153] Compositions more directly inspired by the events include: Todd Rundgren mentioned the Son of Sam on his song "Bag Lady" from his 1978 album Hermit of Mink Hollow.