The shooting
On the afternoon of 21 February 1999, Sillanpää was at a commercial shooting range on Albertinkatu in Helsinki. During a practice session she fired on other people at the range, killing three men. A fourth man suffered serious, lasting injuries, while another person escaped without physical injury.
Police identified Sillanpää quickly. She left the range and was arrested later that day at Helsinki-Vantaa Airport. The pistol used in the shooting was subsequently recovered from a bin at the airport.
Investigation and trial
The case attracted intense attention because no ordinary personal dispute or conventional criminal motive explained the attack. During the proceedings Sillanpää spoke very little, and the court ordered a psychiatric assessment.
In October 1999, Helsinki District Court found her guilty of three counts of manslaughter and two attempted manslaughters. The court also concluded that she had been legally insane at the time of the offenses and therefore did not impose a prison sentence. She was committed to psychiatric treatment.
The appeal
The prosecutor appealed, arguing that Sillanpää should have been considered at least partially responsible and punished with imprisonment. In October 2000, the Helsinki Court of Appeal left the central ruling unchanged: the findings of guilt remained, but so did the conclusion that she was not criminally responsible because of her mental state.
The appeal court also reviewed compensation claims from survivors and victims' relatives. The case therefore ended with judicial findings about the acts themselves while criminal punishment was replaced by compulsory psychiatric care.
Why the case remains notable
The Albertinkatu shooting is remembered as one of Finland's most unusual late-20th-century multiple-homicide cases. Its legal history is especially significant because the courts distinguished clearly between proof that Sillanpää committed the acts and the separate question of whether she could be held criminally responsible for them.
Later retrospective reporting has continued to focus on the surviving witnesses, the rapid arrest and the difficult questions the case raised about responsibility, treatment and public safety.