Born in New York City on November 13, 1960, Bullock had a history of trouble with the law that dated from his adolescent years. In February 1977, he was arrested in Monroe, New York, on charges of criminal mischief and petty larceny. Five months later, in Manhattan, he pled guilty to attempted grand larceny and was committed to a home for delinquent youths, receiving a conditional discharge in November. A burglary arrest in January 1978 led to his adjudication as a youthful offender in Goshen, New York. Over the next three years, Bullock logged adult arrests for robbery and grand larceny, drifting into the seamy underworld of male prostitution. Between December 1981 and January 1982, he killed at least six times, without apparent provocation from his victims.

Number one was 42-year-old James Weber, an actor shot to death in Central Park the evening of December 4. Nine days later, Bullock told prostitute Edwina Atkins about the murder and she "laughed in (his) face," refusing to believe the story. After sex, Bullock covered her face with a pillow, shot Atkins in the head and set her apartment on fire. On December 15, Bullock used a similar method with Stephen Hassell, a 29-year-old businessman who took him home for sex. As Bullock told detectives, there was "no particular reason" for Hassell's murder; it was "something to amuse myself."

Bullock's fourth victim was roommate Michael Winley, shot in the head on December 23 and dumped in the Harlem River. (Police accepted Bullock's version of the crime, despite the fact that Winley's corpse had never been recovered.) Heriberto Morales, age 50, took Bullock home after a Christmas party and paid for the mistake with his life. According to Bullock, Morales "started messing with the Christmas tree, telling me how nice the Christmas tree was, so I shot him." As an afterthought, he also set the place on fire.

Thus far, all of Bullock's victims had been murdered with a .38 revolver, shot without apparent motive. On the fourth of January, Bullock needed cash and he was carrying a sawed-off shotgun when he met 28-year-old Eric Fuller in Mount Morris Park. Charged with six counts of murder on January 15, Bullock told detectives that there might be other victims: he had tried to shoot at least four more, but might have missed. Without specific details, bodies, or complaints from living targets, no more charges were appended to the list.

On October 26, 1982, Bullock pled guilty to six counts of second-degree murder. Asked for a motive, he told the court, "It's fun." To David Bullock, murder was a kind of sport that "makes me happy." Facing terms of 25 years to life on each murder count, he was advised of the judge's intention to mete out a sentence that "guarantees you never get out of jail as long as you shall live.