The convicted man, 27, was also ordered to pay 224,000 kronor ($32,839) in damages to the family of the deceased man, 23-year-old bus-driver Peter Ivansson.
“Peter dreamt of opening his own business with his little brother, but instead they found him in the sewer,” said the victim’s father Inge Ivansson to Expressen newspaper ahead of the verdict.
“The murderer should get a life sentence.”
He also told the paper how the trial has been unbearable at times, stating he was forced to leave the room in horror when pictures of his son’s body being removed from the lake were shown to the court.
The 27-year-old man was formally charged with murder for having strangled Ivansson in his apartment and then dumping the body in the sewer before later moving the corpse to a lake near Karlskrona, southern Sweden.
While he had confessed to parts of the crime, the man also explained that he didn’t remember exactly what happened, according to the TT news agency.
Ivansson was reported missing on August 23rd last year after he failed to show up for his bus driving shift.
On that same day, the convicted murderer had written on the victim’s Facebook page “Where are you?”
Further evidence against the man was strong, as he had told his brother that he had killed Ivansson, as well as written about it in a letter and personal notes.
The browser history of the 27-year-old also revealed that he had searched the internet for information on the penalties for murder.
During the trial, the convicted man confessed that he had a mental image of a belt around his friend’s neck, and also confessed to stealing money from a cupboard in the man’s house.
Ivansson’s body was found in Fabbesjön Lake in Blekinge, southern Sweden, a month after he was reported missing.
While 12 years in prison is the official ruling, the victim’s father claims that anything besides life is a much too lenient punishment.
“He took our boy away from us and we’re in perpetual mourning. Life in prison is the only alternative. He should never get to come out,” he told Expressen.