Laiho, whose fraudulent practice was uncovered in 2011 following an investigation by the Ilta-Sanomat tabloid, was arrested on 7 January and remanded in custody during the preliminary investigation. The probe is expected to take until the end of the spring.
Initial investigations suggest Laiho could be guilty of crimes in several different cases, three of which involved patient deaths. Two of those cases occurred in Helsinki in 2011 and one in Lahti in 2006.
Five other cases are also under review, and patients or their relatives have been informed of all ongoing investigations. Helsinki district court is due to handle his custody hearing on Friday.
In addition to the homicide inquiries, Laiho is also suspected of practicing as a doctor while unqualified, defrauding his former employers and forgery. Those investigations are also expected to conclude in the spring. They are likely to form part of the same trial, where all charges against Laiho will be handled.