The trial begins at Eastern Uusimaa District Court on Thursday of two people charged over the drowning death of a 7-year-old boy in a swimming pool in Porvoo in November 2020.
The child drowned at Porvoo city swimming pool while he was taking part in a supervised after-school programme.
The group included two instructors and ten children, who were moving between a wading pool and the facility's wave pool.
According to investigators, the 7-year-old was initially in the wading pool, but moved to the wave pool and swam to one end where he was soon out of his depth.
Surveillance camera footage from the facility showed that the child was underwater for about four and a half minutes. Attempts were made to revive him after he was pulled from the water, but he died at the scene.
The two after-school club instructors face charges of negligent homicide, as the prosecutor in the case argued they had primary supervisory responsibility for the safety of the children in the group.
The police also looked into the actions of two swimming hall lifeguards and two other people who were in supervisory positions during the course of the investigation, but the prosecutor decided not to press any charges against them.
According to the prosecutor, the sequence of events that led to the child's death is not in dispute.