Justice Andre Wiltens found guilty last month Mr Salwai on perjury charges.
The maximum penalty of perjury charge is seven years.
The Supreme Court found Salwai had misled the court when he said the Council of Ministers had approved a decision to create parliamentary secretary positions.
The case was brought by then-opposition leader Ishmael Kalsakau in November 2019, who said the council had never approved it.
The appointment of parliamentary secretary was challenged by the president of the Republic of Vanuatu.
