The prosecution has charged the three man, who have been remanded in custody since April 2016, of the murders of Philip Rasmussen, 19, Suhaib Jaffar, 23, and Mike Patrick Winther, 24, in an apartment in the neighbourhood during the early hours of 11th November 2015.
The crime has been linked to gangland conflicts involving the Bandidos biker group, reports broadcaster DR, and Frederiksberg Court was full of friends and relatives of the murdered trio, as well as individual with connections to the Bandidos, as proceedings began on Thursday.
According to police, the men's killers climbed a scaffolding to get into the apartment, where they “liquidated” the three victims, the broadcaster reported.
Police have classified the crime as a liquidation since there was no evidence of any struggle prior to shots being fired, reports news agency Ritzau.
The men were found lying on beds and mattresses.
Six shots in total are said to have been fired from a revolver and a shotgun at around 3:40 am. Mike Patrick Winther sent a text message to his girlfriend around an hour earlier saying “sleep well”, according to DR's report.
The three victims belonged to a gang calling itself the Vanløse Group (after a district of Copenhagen, ed.), police said.
The Bandidos group was subject of police investigation shortly after the crime took place, with two locations frequented by the group in Copenhagen ransacked by the police one week after the shootings.
One of the three accused men is a member of the group.
“He denies the charges, and we are looking forward to presenting our side of the case,” the man's defence lawyer Berit Ernst said, according to Ritzau.
A fourth man, also a Bandidos member, was also accused of taking part in the murders committed suicide in custody in June 2016, reports DR.
The other two accused men also deny the charges.
The court is expected to meet up to 20 times before judgement is passed in May.