At the request of his client, Mangs's lawyer filed a petition on Thursday claiming that the lay judge was biased for participating police board meetings during the investigation.
“We consider it to be a conflict of interest and the client wants us to do it,” Mangs's lawyer Jesper Montan said in his request, according to the Sydsvenskan newspaper.
Montan and Mangs's other lawyer Douglas Norking wrote in the filing that the lay judge in question undermined his impartiality and independence by attending the meetings.
“Now there has been a formal objection on the grounds of bias and this shall be communicated to the opposition,” said Eva Wendel Rosberg, head of the Malmö District Court.
The defence laywers accused the lay judge of participating in meetings with police on three occasions during the autumn of 2010, thereby gaining access to information that made it questionable whether he could make an unbiased review of the police investigation.
The lay judge will meet with Malmö District Court head judge Lennart Strinäs in an attempt to better assess the question of bias.
Mangs was arrested in November 2010 after a string of shootings that took place in Malmö against people of immigrant origin.
He was charged with killing two men of immigrant origin, aged 23 and 66, in 2003 and a 20-year-old Swedish woman who had been sitting in a car with an immigrant man in 2009.
He was also charged with 12 attempted murders in which he fired numerous shots with his Glock 19 pistol at homes, businesses and cars as well as out in the open, seriously injuring a number of people and coming close to killing many others.
In July, after a highly publicized trial and a lengthy criminal investigation, the court ruled that he was guilty of 13 of the charges, among these two murders, four attempted murders and three cases of making illegal threats.