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 Fesch planned a robbery to fund a sailboat he wanted to buy. He and his friend, Jacques "Criquet" Robbe, went to the Comptoir de Change et de Numismatique money changer office in Paris. Fesch pulled out a revolver and locked the door. When the elderly shopkeeper, Alexandre Silberstein, tried to reason with him, Fesch attacked Silberstein, hitting him twice with the gun.

During the robbery, Silberstein managed to raise the alarm, which startled Fesch. In the chaos, he dropped his gun and accidentally shot himself in the hand while trying to retrieve it. Despite his injury, Fesch took 300,000 francs from the cash register and fled. He was chased by people in the street but escaped by hiding in an apartment building.

A concierge in the building saw Fesch enter and informed police officer Jean-Baptiste Vergne. A crowd gathered as Fesch tried to sneak past them. When Vergne ordered him to surrender, Fesch fired his gun without aim. The shot hit Vergne in the heart, killing him instantly. Fesch also injured a passerby during his escape. After more gunfire, he ran into a metro station but was overpowered and arrested by a bystander.

Once in custody, Fesch confessed to the robbery and the murder of Vergne, showing no remorse for his actions. The public outcry against him was severe, and he was tried for the murder of the police officer. Fesch was found guilty and sentenced to death on April 6, 1957.

Fesch experienced a religious conversion while in prison. He began to regret his actions and expressed a desire to ask for forgiveness from the families of his victims. His appeal for clemency was denied, and he was executed by guillotine on October 1, 1957.