Kaj Linna was sentenced to life in jail over a brutal combined robbery and murder in Kalamark in the far north of Sweden in 2004, despite a lack of forensic evidence or an eye witness linking him to the scene.

He always denied having committed the murder and at the end of last year, after new evidence was presented in a Swedish crime podcast based on global phenomenon 'Serial', he was granted a retrial.

On Thursday the court formally cleared Linna of all charges, confirming what it had indicated at the end of the trial last month when it released him pending the verdict.

The judge of the court of appeals for Övre Norrland, Margareta Bergström, said in a statement: “Our conclusion is that the evidence presented in the trial is insufficient and therefore cannot lead to conviction.”

Linna's case dates back to April 2004, when two brothers were attacked on a farm some 20 kilometres from Piteå. One of the brothers was killed; the other was assaulted but survived. The latter, who was disabled because of a stroke, was found by social services two days later and said he had recognized the voice of a man who had previously done business with the brothers and who they perceived as threatening.

The man, who had an alibi, instead mentioned Linna as a potential suspect and pointed police in the direction of another man who had more information. That man became the main witness at the trial and said Linna had told him of plans to rob the brothers.

Linna's fight for a retrial has been a long-running feature in Swedish media, with newspaper DN's reporter Stefan Lisinski one of those who had pointed out several errors and gaps in the main witness' story. The Supreme Court ordered the appeals court to retry the case last year after the same witness, speaking to Swedish crime podcast Spår, changed the details of the account he gave to the police. The witness had also offered new information in a documentary about the case by Swedish filmmaker Mårten Barkvall.

“My time in jail was completely wasted, worthless,” commented Linna on Thursday. He has previously said he intends to seek damages from the Swedish state, but added money could not repay him for the time lost.

Nonetheless, he is likely to be awarded significant payouts, legal experts agreed. In a similar case, Joy Rahman, a Swedish-Bangladeshi man who spent eight years in jail over a woman's murder, received 10.2 million kronor in damages after it was found in 2002 that he had been wrongfully convicted.

“I would be surprised if Kaj Linna's compensation does not break the record,” law professor Mårten Schultz of Stockholm University told Swedish news agency TT.

Created by Swedish podcast platform Acast and hosted by Anton Berg and Martin Johnson, Spår was launched in 2015 to take a closer look at the case in its first five-episode season, inspired by the hugely popular US investigative podcast Serial.

“Spår hosts Anton and Martin should be amazingly proud that their series has helped bring about justice for Kaj Linna and that he can now walk free, though the tragedy of the last 13 years can never be undone,” Karl Rosander, Spår executive producer and co-founder of Acast, told The Local on Thursday.

“This result is a landmark moment for podcasts as a cultural phenomenon. It shows that not only can podcasts inform and entertain, but they can also form investigations that shape real-life events.”