Duponchee, who had just turned 18 at the time of the events, ambushed the mayor and slit his throat with a utility knife before calling the emergency services to the scene.
The murder of Gadenne, a well-loved mayor who reportedly had the habit of closing the cemetery gates each night, shocked the community of Mouscron, a city in the province of Hainaut located near the border with France.
Still present on the scene when the police showed up, Duponchee reportedly told them there was “no use” in checking on the mayor since he “was already dead,” and said he had killed him to “avenge his father,” according to reports by RTBF.
Throughout the subsequent investigation, Duponchee said that he saw Gadenne as responsible for the suicide of his father, who hanged himself in 2015, when the accused was 15 years old.
The defendant’s father committed suicide after his contract as a local employee for the federal ministry of the interior, for whom he worked for ten years, was not renewed.
“In my eyes, my father killed himself over his job,” Duponchee told the courtroom during his address on Monday, according to La Dernière Heure.
Noting that his father would often come home from work stressed and complaining of arguments with his superiors, he said he saw his father’s fate as ultimately resting in the mayor’s hands.
“The person who could have helped my father keep his job —he who made the final decision—was the mayor,” he said.
The opening hearing on Monday in Hainaut’s criminal court kicked off with the designation of a twelve-person jury, made up of six women and six men, selected randomly out of a pool of over a hundred candidates.
Duponchee stands accused of murder, after investigators found his acts were premeditated, upon discovering he had done research into prison terms for murder or prison conditions in Belgium, as well as talked of his plans over text message.
He faces additional charges for attempting to escape while wearing an ankle bracelet while armed with a knife in 2018, RTBF reports.
The trial is expected to last throughout the week, if found guilty, the defendant risks life in prison.