Jacques Fesch was born on April 6, 1930, in Saint-Germain-en-Laye, France. He was the only son of Georges Fesch and Athalie "Marthe" Hallez. Georges, his father, was a wealthy banker of Belgian descent who claimed ties to the Fesch noble family. He was also an artist and an atheist. He was often distant from Jacques, which may have affected their relationship. Jacques had two older sisters and was very close to his mother, who was a devout Catholic.

From 1938 to 1947, Jacques attended Catholic schools, Saint-Érembert School and Claude-Debussy High School. Although raised as a Catholic, he stopped practicing his faith by the age of 17, particularly after his parents divorced. He was expelled from high school that same year for being lazy and misbehaving. Without a diploma, Jacques started going to jazz clubs in Paris, where he gained a reputation for being a womanizer.

After his studies, Jacques completed his military service in West Germany from 1950 to 1951. He achieved the rank of corporal and received a good conduct certificate, although he was noted as a poor marksman in his military records. On June 5, 1951, Jacques married Pierrette Polack, a girlfriend who was pregnant at the time. The couple was married in a civil ceremony in Strasbourg. Pierrette and her parents were Catholic, but Jacques's parents disapproved of the marriage because Pierrette's father was ethnically Jewish.

The couple lived with Pierrette's parents, and Jacques got a job working at a coal delivery business owned by his father-in-law. However, he embezzled money from this job and spent it on luxury items and to impress women with whom he was having affairs. Jacques's mother later offered him a sum of money to start his own coal business, wanting him to distance himself from his in-laws. He accepted the money, used some of it to buy a car, and squandered the rest on his lifestyle.

In 1952, Jacques's dishonesty was discovered, leading to him being thrown out by his in-laws. He then reconciled with his parents and took a job at his father's bank. In December 1953, he met Thérèse Troniou, with whom he had an illegitimate son named Gérard, who was placed in foster care. After losing his bank job, Jacques became interested in sailing. He read books that inspired him to dream of escaping to the South Pacific, although his parents refused to help him buy a boat. He decided to construct a sailboat in La Rochelle, but his life took a different turn from there.

On February 24, 1954, Jacques On February 24, 1954, Jacques Fesch attempted to rob the Comptoir de Change et de Numismatique, a Parisian money changer’s office located in the 2nd arrondissement. He had ordered gold coins and ingots totaling 2 million francs, intending to steal them using a revolver he had stolen from his father. His childhood friend Jacques “Criquet” Robbe accompanied him under the false impression that they were simply collecting money. Upon realizing the robbery was taking place, Robbe fled the scene and shouted for help in the street.

Fesch entered the office and confronted Alexandre Silberstein, the elderly money changer, demanding the gold. When Silberstein pleaded with him to reconsider, Fesch pistol-whipped him twice, causing him to fall. The commotion triggered an alarm, and in the chaos, Fesch accidentally shot himself in the left hand while retrieving the revolver he had dropped. He stole 300,000 francs in cash instead and fled the scene.

Fesch ran through the Boulevard des Italiens, trying to evade pursuit, but had lost his glasses, which severely impaired his vision. He hid in a residential building at 9 Boulevard des Italiens. A concierge, suspicious of his behavior, flagged down Officer Jean-Baptiste Vergne, who entered the building to investigate. When Vergne confronted Fesch, the fugitive fired blindly through his coat, striking Vergne fatally in the heart. As bystanders attempted to intervene, Fesch shot another man, Raymond Lenoir, in the neck and fled toward the Richelieu-Drouot metro station. However, the gates were closed. He was ultimately tackled and disarmed by Georges Plissier, a 28-year-old passerby.

Fesch was arrested on the spot and taken to 36, quai des Orfèvres for interrogation. During questioning, led by Chief Inspector Max Fernet, Fesch confessed to the robbery and the killing of Officer Vergne but showed no remorse and lamented only that he had been caught. Evidence showed that he had removed the safety catch from the revolver, supporting the conclusion that he acted with lethal intent. His motive was confirmed to be the purchase of a sailboat to sail to Tahiti.

Public reaction to the murder of a police officer was furious and unforgiving. Newspapers portrayed him as a cold-blooded killer, and pressure from police unions reportedly influenced the court. On April 6, 1957, the Cour d’assises of Paris sentenced Fesch to death by guillotine. Appeals for clemency, including one to President René Coty, were rejected. His accomplices, Robbe and Jean Blot, were acquitted.