The court in the state of North Rhine-Westphalia found the boy guilty of causing life-threatening injuries to the girl – identified only as Kassandra – by hitting her in the face with rocks, then putting her 1.5 metres below ground in a drain pipe with a heavy manhole cover on top.
She was found in critical condition by a search dog after lying in the pipe for seven hours. Her injuries were so severe that doctors put her in an artificial coma for several days so she could heal. When she awoke she reportedly had no memory of the attack.
The day before the attack she had attended a Catholic youth group meeting but did not return home, prompting a call to the police from her worried parents.
Four weeks of court proceedings against the underage defendant, who according to daily Bild had attended a special school for adolescents with emotional problems, were closed to the public.
After denying wrongdoing to police, the boy is said to have spoken about the September 14, 2009 crime for the first time during this month, and his lawyer said the statements were a confession.