An appeals court in Helsinki has acquitted several top police officers of misconduct charges relating to the registration of informants by corrupt narcotics officer, Jari Aarnio.
The former National Police Commissioner Mikko Paatero, current head of Helsinki police department Lasse Aapio and Robin Lardot, who heads up the National Bureau of Investigation (NBI) were all acquitted of misconduct charges over their oversight of narcotics informers and their registration.
Prosecutors had asked for suspended jail sentences in the case.
The court did hand down guilty verdicts for former head of Helsinki police Jukka Riikonen and Aarnio himself, along with one of his subordinates.
Aarnio was not sentenced, as the court viewed his multiple other jail terms as sufficient punishment, but the other two were fined by the court.
Helsinki District court had previously acquitted all those accused because they had been unable to register informants properly, but the prosecutor appealed that verdict.
The appeals court took the view that there had been no legal or practical obstacle to properly registering informants in the Helsinki Police department system.
The investigation started in 2013 when then-Interior Minister Päivi Räsänen (CD) reported the matter to prosecutors.