German serial killer known as the 'Masked Man' faces verdict in France over 2004 murder of 10-year-old boy

In Germany, Martin N. is known to the press as the "Maskenmann" — the Masked Man — or "schwarzer Mann," the Black Man. A court in Lower Saxony sentenced him to life imprisonment in 2012 for the murder of three boys and for child sexual abuse. Police have attributed more than 40 sexual offenses against children to him, and investigators recovered thousands of child pornography images from his computer.

The German convictions

The German killings spanned nearly a decade. Martin N. committed his first murder in 1992 at the age of 21, when the victim, a 13-year-old boarding school student, was found in a dune in Lower Saxony with his hands tied behind his back. Two more boys were killed in northern Germany in 1995 and 2001, their bodies hidden or buried many kilometers from the crime scenes. The three German victims were aged between 8 and 13.

German police set up a special commission in 2001 after the killing of Dennis K. that year. The breakthrough in the case came in 2011, when an adult former abuse victim recalled being questioned as a child by a caregiver named Martin about his home, and later waking to find a tall man dressed in black with a balaclava in his room. After his arrest, Martin N. confessed to killing the three boys.

How the suspect was caught

According to the court's view reported by NDR, Martin N. killed his victims to prevent his sexual preference for boys from being exposed. The presiding judge in the German proceedings, Berend Appelkamp, stated that Martin N. particularly feared the ostracism of his mother. "Insbesondere fürchtete er die Ächtung seiner Mutter. Diese Aufdeckung wollte er mit allen Mitteln verhindern," the judge said. Before turning to crime, Martin N. had studied to become a teacher without success and later worked in adult education and as a youth counselor.

The French investigation into Martin N. began in 2008, when authorities noted parallels between the Brittany killing and his series of crimes in northern Germany. Martin N. reportedly confessed to a fellow inmate that he had killed a child in France, and a witness told investigators he had seen a car with German license plates near the pond after the 2004 murder, whose driver appeared to want to unload something before driving away. No concrete evidence such as DNA traces has been found linking him to the French crime, however.

The French case

Unlike the German cases, Martin N. has not confessed to the murder in France and has repeatedly denied involvement. In court, he said "Ich habe das nicht getan." The prosecution has nevertheless demanded a life sentence, with the prosecutor general telling the court: "Ich habe keinerlei Zweifel daran, dass er schuldig ist." The newspaper Le Figaro reported from the courtroom as closing arguments were heard.

A verdict is expected in the evening of the same day, according to court officials. The defense's closing arguments are scheduled for the afternoon. If convicted, Martin N. would face a second life sentence, to be served in addition to the one already being served in Germany.