Hudiksvall delivered the final verdict on Thursday, sentencing Fagerström to life in prison.
It found him guilty of murder, assault, coercion and threats, according to the verdict seen by The Local.
The body of Moberg, from the small town of Njutånger in Hudiksvall municipality, east-central Sweden, was found hidden in a lake in May last year in a case that shocked the local community. A few days earlier, she had been reported missing by her family after she failed to return home after a party.
Her ex-boyfriend, who was 22 years old at the time, was shortly thereafter arrested on suspicion of killing her. Fagerström had previously been reported to the police for assaulting her, and she had recorded several violent incidents in her diary, which was used as evidence in the trial which ended in late 2017.
The court said her diary had made a big impression on them. “These notes showed that the woman predicted that the man might kill her, which tragically proved to be true,” said judge Bengt-Olov Horn in a statement.
Billy Fagerström in court. Photo: Mats Andersson/TT
An examination of the body showed that Moberg had been strangled and hit 20 times with a hammer. Police found blood stains outside Fagerström's house and found that he had attempted to burn his clothes. However, no DNA traces were found on her body.
Hudiksvall District Court last year ordered Fagerström to undergo a comprehensive psychiatric evaluation before it could deliver its sentence, which experts at the time said suggested a guilty verdict.
The evaluation later found he was not suffering from serious mental disorder at the time of the crime, which means the court could sentence him to prison rather than closed psychiatric care.
The prosecutor has urged the court to lock him up for life. Fagerström had denied the charges.